# Implementation summaries

## incremental-captures (2026-07-21)

Built per `plan/incremental-captures.md`: download captures are now
**incremental and resumable**, uncapturable tracks are first-class
**skipped** entries, and captures stream **progress** to clients.

- **Skipped playable (fsdy + proto).** `[playable] skipped = true` is a
  fourth, mutually exclusive playable; `Playable::Skipped`,
  `from_track_skipped`, and a new wire flag `Track.is_skipped` (set by
  `to_track`). `from_track` preserves skipped-ness, so persisted queues
  and bookmarks keep the marking instead of degrading it into a dead
  link. `get_urls_for_track` on a skipped file is a typed `FetchError`.
- **Incremental walk.** The shared capture walk now runs in two phases:
  enumerate (dirs + tracks, caps enforced — the total is known before
  the first download) then fetch. `Sink::Download` writes straight into
  `captures/<name>` (no tmp/swap): satisfied entries — parseable toml,
  non-skipped playable, audio present — are reused; skipped, broken, or
  audio-less entries are re-captured; uncapturable sources (skipped
  source track, unresolvable stream, non-http playable) are recorded as
  skipped tomls instead of silently omitted; a real download failure
  aborts the run but keeps everything written, so re-capturing the same
  name resumes. The byte budget counts only bytes downloaded per run.
  Bookmarks keep tmp-and-swap overwrite semantics unchanged.
- **Progress + accept-then-stream RPC.** New `CaptureProgress` update on
  the stream (name, download, done/total/skipped, terminal
  finished/error). `CaptureLibraryNode` replies once validation (name,
  store, download blessing) passes; the walk runs detached and its
  bounded progress channel is forwarded into the update broadcast. This
  also unfreezes the TUI: its poll loop used to await the whole capture.
- **Playback.** `play` skips `is_skipped` tracks without a provider round
  trip and bounds the whole skip loop to one full queue pass — an
  all-skipped queue with repeat on now stops instead of hammering the
  provider forever (pre-existing spin fixed).
- **TUI.** Skipped tracks render red in queue and library (playing-track
  marker keeps precedence). A `CaptureBoard` renders progress lines at
  the bottom of the library pane (`capturing faves 3/12 (1 skipped)`),
  lingering 5 s on success and 10 s (red) on failure. The `W` help entry
  and the capture input label warn that captures are slow and resumable.
  Contrast fix: colored items (editable/marked/skipped/current) switch to
  the dark foreground under the focused selection bar.

Deviations from the architecture doc: `tracks_done` counts skipped
entries too (the ratio must reach the total on success) — doc and proto
reconciled; the input-overlay warning was shortened to
"capture (slow, resumable)" to fit narrow panes. `taplo` reports a
pre-existing formatting issue in `.opencode/skills/skill-authoring/`
(not touched here). 167 workspace tests green (13 new);
every gate in `quality/incremental-captures.md` checked.

## cbd-bundle (2026-07-21)

Built per `plan/cbd-bundle.md`: a new **`cbd`** binary bundles server
and TUI. Both former binaries became libraries with thin mains —
`crabidy_server::serve(addr)` is the extracted server startup
(orchestrator, queue store, playback, player forwarder, tonic), and
`cbd_tui::run(config)` the extracted client loops; the standalone
binaries behave exactly as before. `cbd` sets up one file-based tracing
subscriber for both halves (the terminal belongs to the TUI), spawns
`serve` on the fixed listen address, polls a TCP connect against the
TUI's configured server address until ready (bounded, generous — first
runs may sit in a provider login), then runs the TUI. An
already-running standalone server just gets adopted (the in-process
bind fails on the occupied port and is deliberately ignored once the
socket is reachable); a server that dies before readiness surfaces its
real error. Quitting the TUI ends the process and the in-process
server — the continuously persisted current queue makes that safe.

Deviations: none of substance — the refactor moved code verbatim
(`crabidy_server::` → `crate::` path rewrites aside). The live probe
booted the extracted stack on a free port through the same readiness
poll `cbd` uses: real tidal login, all providers, playback, queue
restore, TCP accept in ~1 s (probe removed after passing). 154
workspace tests green (2 new in `cbd`); every gate in
`quality/cbd-bundle.md` checked.

## captures follow-up: W on queues and bookmarks (2026-07-21)

Small fix on top of the captures feature: `/queues` and `/bookmarks`
nodes are now `W`-capturable. `fsdy::Client` gained
`with_downloadable_nodes()` (instance-wide `is_downloadable`, applied to
the queues and bookmarks mounts; `/fs` and `/captures` stay off), and
the download sink softens all-or-nothing for exactly one case: a track
whose source cannot be captured — stream resolution fails, or resolves
to a non-http(s) target like a local file playable — is skipped with a
warning instead of aborting, since queue/bookmark captures mix
providers. Real download failures (bad status, transport, timeout) stay
fatal. `architecture/captures.md` D3/D4 reconciled; new tests
`downloadable_instances_flag_every_node` (fsdy) and
`download_capture_skips_uncapturable_tracks` (capture store).

## youtube-provider (2026-07-21)

Built per `plan/youtube-provider.md`: a new workspace crate **`ytdy`**
mounts YouTube at `/youtube`, backed by a `yt-dlp` subprocess (declared
in `devenv.nix`). All extraction goes through one `Engine` seam:
argv-only invocations with `--no-warnings`, an optional `--cookies`
flag, a per-call timeout (`kill_on_drop`), a 32 MiB stdout cap, and
typed `EngineError`s — tests drive the whole provider through a fake
shell-script binary, no network.

Search needs no login and mirrors tidal's search exactly: `%` on
`/youtube/search` creates an in-memory term (deduplicated, implicitly
recreated on stale paths, rename re-searches, delete idempotent), whose
node lists the top N (`ytsearchN:`, default 20) results as queueable,
downloadable tracks. With a readable cookies file configured in
`ytdy.toml` ("logged in"), a `playlists` subtree appears
(`feed/playlists` flat listing → playlist nodes with tracks); an
unreadable cookies file degrades to logged-out with a warning, never a
failed init. Streams resolve via `-f bestaudio/best -g`; captures work
end to end (`extension_for` gained `audio/webm → webm`). The
orchestrator wires `/youtube` non-fatally: a failed `--version` probe
disables the provider, nothing else.

Deviations: `Entry` keeps separate `uploader`/`channel` fields with an
`artist()` preference — the planned serde alias rejects real yt-dlp
output as a duplicate field (found by the live probe). The live probe
validated search, stream resolution, and a real download capture
(252 KB webm) through the capture store; the **playlists feed
invocation is live-unvalidated** (no cookies on this machine) — flagged
in `architecture/youtube-provider.md` as the standing risk. 150
workspace tests green (8 new in `ytdy`); every gate in
`quality/youtube-provider.md` checked.

## captures (2026-07-21)

Built per `plan/captures.md`: `W` (shift) on a downloadable library
selection captures the subtree like a bookmark, but into
`<config>/crabidy/captures/<name>/` with every track's audio
**downloaded** next to its order-prefixed toml — the toml's playable is
the audio file's *relative* name (`TrackFile::from_track_with_file`), so
a capture plays with no provider round trip and the folder stays
relocatable. `/captures` is a fourth `fsdy` instance (editable top
level, nothing reserved): browse, queue, rename (`e`), delete (`d`),
and re-capture to refresh; the audio files are invisible to listings
(only dirs and `*.cbd-track.toml` count).

The bookmark walk was extracted into `capture.rs`
(`capture_into`/`write_tree`, `Caps`, one `CaptureError` for both
stores) parameterized by a per-track `Sink` — `Link` is byte-identical
bookmark behavior, `Download` fetches the first `get_urls_for_track`
URL through one shared reqwest client (30 s connect timeout, 600 s
per-track deadline, no retries), streams the body to disk against a
capture-wide byte budget, picks the extension from `Content-Type` (URL
path, then `bin`, as fallbacks), and writes the toml only after the
audio succeeded. Download caps: 1 000 dirs, 500 tracks, 4 GiB. Still
all-or-nothing with temp cleanup; downloads are sequential inside the
one spawned capture task. Download error messages carry the track's
library path, never the stream URL (`reqwest::Error::without_url`).

Nodes opt in via new additive proto flags
(`LibraryNode.is_downloadable = 8`, `LibraryNodeChild = 7`). Tidal sets
them centrally at the end of `get_lib_node`: downloadable = queueable
**or lists tracks** (so search-term track results are downloadable even
though the term node isn't queueable); children mirror `is_queable`;
tracks inherit their node's flag in the TUI. The server re-enforces at
the capture root (`Unsupported` → `failed_precondition`); the rpc
gained `CaptureLibraryNodeRequest.download = 3` (additive; old clients
keep bookmarking).

Deviations from the plan/architecture: the naming helper ended up
`audio_file_name` (the path variant was clippy-dead); the tidal flag
rule grew the "or lists tracks" clause (architecture D4 reconciled);
the live probe downloaded a single real track (8.6 MB m4a,
Content-Type-derived extension, replayed through a `/captures`
instance) instead of a whole album — the multi-track walk is
unit-covered and a full album download is needlessly heavy for a smoke
test. 142 workspace tests green (1 new in `fsdy`, 8 in
`capture`/`capture_store`, 3 TUI + 1 extended); every gate in
`quality/captures.md` checked.

## bookmarks (2026-07-21)

Built per `plan/bookmarks.md`: `w` on a queueable library selection now
captures the whole subtree as a **bookmark** — a structure-preserving
snapshot under `<config>/crabidy/bookmarks/<name>/`, mounted read-only at
`/bookmarks` by a third `fsdy` instance. The capture runs on the
orchestrator (a spawned task walking `get_lib_node` iteratively across
any provider): every child node becomes an order-prefixed folder
(`fsdy::dir_name`, sharing the queue entries' sanitizer), every track an
order-prefixed link file, so the case-insensitive listing reproduces the
source order and replaying is plain fs-provider behavior. Caps (1 000
dirs / 20 000 tracks) abort cleanly with the temp folder removed; writes
are tmp-and-swap; re-capturing a name overwrites it. The wire gained one
additive rpc, `CaptureLibraryNode(path, name)` (invalid name/source →
`invalid_argument`, over-cap/disabled → `failed_precondition`). The TUI
opens the existing input overlay prefilled with the selection's title
(`bookmark`), gated on a queueable bare selection.

On top, `fsdy::Client` gained `with_editable_top_level(reserved)`:
editable instances mark their root's child folders
`is_editable`/`is_deletable` and implement rename (no-merge, validated
titles, returns the renamed node) and delete (idempotent, returns the
refreshed root). Applied to `/bookmarks` (nothing reserved) **and
`/queues`** (reserved: `current`) — saved queues are now renamable and
deletable through the existing `e`/`d` flows with zero TUI changes.
`/fs` stays immutable. All 130 workspace tests green (6 new in `fsdy`, 7
in `bookmark_store`, 2 TUI); every gate in `quality/bookmarks.md`
checked. A temporary live probe (removed after passing) captured a
19-track album from the live Tidal API, browsed it with editable flags,
renamed it, resolved it in order, and fetched a stream URL for a
captured link.

The whole feature ran autonomously per standing instruction; decisions
are recorded in `architecture/bookmarks.md` (options + rationale).

### Deviations from plan / architecture (bookmarks)

- **Capture is all-or-nothing**: any provider or write failure mid-walk
  aborts the whole capture (temp folder removed) instead of skipping the
  failing subtree with a warning — a bookmark that *looks* complete must
  *be* complete. The architecture only specified the unreadable-*root*
  case; this extends it to every node.
- **Rename to the current name is a no-op success** (returns the node),
  not a collision error — the target "exists" only because it is the
  source.
- **Rename targets don't pass `disk_path`**: the new folder name is
  validated by `validate_folder_name` (no separators, NUL, or leading
  dots), which makes it a plain sibling name by construction; the
  traversal gate still covers every client-supplied *path*.
- **`track_file_name` was refactored onto a shared `ordered_name`**
  helper rather than duplicated for `dir_name` (planned as "shared
  sanitizer", realized as one function).
- **Environment note**: builds/tests again ran with a session-local
  `CARGO_TARGET_DIR`; no repo change.

## queue-persistence (2026-07-21)

Built per `plan/queue-persistence.md`: queues now survive server restarts,
realized entirely on top of the fs provider. `fsdy::Client` became
instance-mountable (`Client::new(provider_root, disk_root)`); the
orchestrator mounts a second, read-only instance at `/queues` over
`<config>/crabidy/queues/`, so saved queues are ordinary browsable,
queueable library folders. Every queue is a folder of order-prefixed
(`0001 <title>.cbd-track.toml`) **link** files — metadata copied from the
queue entry, `playable.link = Track.path` — written only by the new
`crabidy_server::queue_store::QueueStore` (tmp-and-swap, hidden
`.queue-state.toml` sidecar for position/repeat/shuffle). The playback
loop feeds every queue-state change into a latest-wins `watch` channel; a
persister task debounces, skips unchanged snapshots, and rewrites
`queues/current/`. On startup the server restores tracks, position, and
modifiers from `current/` without ever starting playback. `w` on the TUI
queue pane opens the existing input overlay (`save queue`) and drives the
previously stubbed `SaveQueue` rpc (invalid name → `invalid_argument`,
empty queue/disabled persistence → `failed_precondition`). Reloading a
saved queue is just queueing `/queues/<name>` — the listing rewrites each
link back to its target, so zero new resolve mechanisms. All 116
workspace tests green (10 new in `fsdy`, 9 in `queue_store`, 5 playback,
3 TUI); every gate in `quality/queue-persistence.md` checked. A temporary
live probe (removed after passing) round-tripped a mixed queue — a track
fetched from the live Tidal API plus an fs url track — through persist,
reload, `/queues` listing, and the resolve walk, and the reloaded Tidal
path still yielded a stream URL.

The whole feature ran autonomously per standing instruction; decisions
are recorded in `architecture/queue-persistence.md` (options + rationale).

### Deviations from plan / architecture (queue-persistence)

- **The "no links into `/fs`" rule was dropped** (fs-provider D3): queue
  entries persist as links to whatever path the queue held, including
  `/fs/...` tracks. Replaced by the one-hop argument —
  `get_urls_for_track` never follows a link, so chains die at play time
  and cycles cannot recurse. `architecture/fs-provider.md` reconciled.
- **`SaveQueueError` gained `Disabled` and `State` variants** beyond the
  stub: `Disabled` (no usable queues directory) maps to
  `failed_precondition` instead of masquerading as I/O; `State` covers
  sidecar serialization.
- **The orchestrator mounts `/queues` independently of `QueueStore`**:
  both derive the directory from `queue_store::queues_dir()`, so a
  mount over a not-yet-created folder simply lists as missing until the
  store (created in `main`) writes it. No plumbing between the two.
- **Shuffle order is not persisted** (documented in D3/D4 but worth
  repeating): restoring `shuffle = true` reshuffles around the restored
  current track.
- **The live probe needed no bespoke server run**: provider-layer clients
  plus `QueueStore` cover the full D2/D5 story; the gRPC and TUI layers
  above are unit-tested.
- **Environment note**: builds/tests again ran with a session-local
  `CARGO_TARGET_DIR`; no repo change.

## fs-provider (2026-07-21)

Built per `plan/fs-provider.md`: a second media provider (crate `fsdy`,
`/fs`) that walks one configured root directory and treats
`*.cbd-track.toml` files as serialized track nodes — metadata plus exactly
one playable reference: a local audio file (absolute or relative to the
track file), an http(s) URL, or a crabidy-internal link. The wire types
are unchanged (architecture D1): the only new datastructure is the
on-disk TOML schema. Link tracks rewrite `Track.path` to the target at
listing time (D2), so playback routes to the owning provider through the
orchestrator's existing prefix routing with zero new mechanisms; links
into `/fs` are rejected at parse time, making chains impossible.
Directories list sorted and queue via the default chunked resolve walk;
client paths are decoded and validated in a single helper so they cannot
escape the root; symlinks, hidden entries, and broken files are skipped
with warnings. `ProviderOrchestrator` gained an optional fs client
(non-fatal init from `fsdy.toml`, default root `dirs::audio_dir()`) and
`/fs` routing arms in every trait method. No player or TUI changes were
needed. All 91 workspace tests green (15 new in `fsdy`); every gate in
`quality/fs-provider.md` checked. A temporary live probe (removed after
passing) built a real tree whose link track pointed at a track fetched
from the live Tidal API: listing order held, the link path was
rewritten, and the target resolved a stream URL — the full D2 story
end-to-end.

The whole feature ran autonomously per standing instruction; decisions
are recorded in `architecture/fs-provider.md` (options + rationale).

### Deviations from plan / architecture (fs-provider)

- **Extension renamed to `.cbd-track.toml`** (user request, follow-up
  commit): the original `.track.toml` was too generic; the `cbd-` prefix
  makes the files unmistakably crabidy's.
- **`TrackFileError::UrlScheme` carries only the scheme**, not the URL:
  the parse error ends up in skip-warnings, and a private stream URL may
  embed a token (quality gate "no file contents in logs"). The
  architecture's schema and behavior are otherwise as designed.
- **The live probe ran at the provider layer**, not against a running
  server (no interactive terminal/audio device here, same as previous
  features): `fsdy` and `tidaldy` clients driven directly, mimicking the
  orchestrator's routing exactly. It also had to *fetch* its link target
  first — the well-known id from the progressive-queueing probe is an
  album path, and a link must point at a track.
- **`get_lib_node` on a track path is `MalformedPath`** — implicit in
  the design, made explicit so the default resolve walk can never
  mistake a track file for a directory.
- **Environment note**: builds/tests again ran with a session-local
  `CARGO_TARGET_DIR` (owner-built artifacts in `target/`); no repo
  change.

## progressive-queueing (2026-07-21)

Built per `plan/progressive-queueing.md`: queueing a large nested collection
now fills the queue progressively instead of freezing until the full
resolve. `ProviderClient` gained `resolve_tracks_into` (chunk-streaming over
a bounded channel; sender-drop = done, receiver-drop = cancel) with a
default pre-order walk; tidaldy overrides it so playlists and albums emit
one chunk per fetched 50-track page. The playback loop registers a pending
op per queue command, spawns a forwarder, applies chunks on the loop
(single-writer preserved), broadcasts after every chunk, and starts playback
with the first chunk that makes a track current. `Replace`/`Clear` cancel
in-flight resolves down to the HTTP fetch. The wire gained
`Queue.resolving = 4` (additive); the TUI renders an animated one-to-three
dots pseudo-item after the last queue row while it is set. All 76 workspace
tests green; every gate in `quality/progressive-queueing.md` checked.
Verified against the live Tidal API with a temporary ignored probe (removed
after passing): a 71-album artist streamed its first 19-track chunk (first
album, listing order) while the walk was still running, and dropping the
receiver mid-stream ended the resolve cleanly in 1.8 s instead of draining
the discography.

The whole feature ran autonomously per standing instruction; decisions are
recorded in `architecture/progressive-queueing.md` (options + rationale).

### Deviations from plan / architecture (progressive-queueing)

- **`make_paginated_request_into` became `stream_track_pages_into`**: the
  planned generic `AsyncFnMut` page sink dies on a rustc
  "implementation of `Send` is not general enough" limitation inside
  `async_trait` methods. The concrete method (fixed `Track` item type,
  proto mapping and channel send inlined) sidesteps it with the same
  page-loop and cancellation semantics.
- **Zero-track warning lives in the forwarder, not `finish_resolve`**: the
  forwarder sees each path and its chunk count, so the existing per-path
  "resolved to no playable tracks" message survives verbatim; the planned
  op-level warning would have had to smuggle paths into `PendingResolve`.
- **Fixed alongside (user-reported)**: Enter on a non-queueable library
  item used to blank the queue while audio kept playing. Two causes, both
  fixed: `Library::get_selected` now gates the bare selection on
  `is_queable` (marks were already gated), and a replace that resolves to
  zero tracks no longer touches the queue at all — structurally, since the
  queue is only mutated by arriving chunks. Regression test
  `queue_ops_ignore_non_queueable_selections`.
- **`Queue` (play-next) captures the current position when the command
  arrives**, not per chunk: chunks of one op stay contiguous after the
  track the user was on when they pressed the key, even if playback
  advances mid-resolve.
- **Live probe scope**: the first full-discography probe was cut short
  (hundreds of album fetches for no extra signal) and replaced by a
  receive-two-chunks-then-cancel probe — which also exercises mid-stream
  cancellation against the live API, which the drain-everything version
  could not.
- **Environment note**: builds/tests again ran with a session-local
  `CARGO_TARGET_DIR` (owner-built artifacts in `target/`); no repo change.

## node-editing (2026-07-20)

Built per `plan/node-editing.md`: search-term nodes (created via `%`) are now
modifiable — `e` opens the input overlay prefilled with the current title and
renames (re-running the search; merge on title collision), `d` deletes
without confirmation (documented decision, architecture/node-editing.md D4).
Capabilities travel as `LibraryNodeChild.is_editable`/`is_deletable` (fields
5/6, child-only — no consumer for node-level copies), surfaced as a `[ed]`
marker; two new rpcs `RenameLibraryNode` (returns the renamed node, TUI
navigates into it) and `DeleteLibraryNode` (returns the refreshed parent).
All 59 workspace tests green; every gate in `quality/node-editing.md`
checked. Verified against the live Tidal API with a temporary ignored probe
(removed after passing): create `beatles` → rename to `rolling stones`
(in-place, 20 tracks / 40 children) → a track queued under the old term
still resolved a stream URL → delete emptied the listing.

The whole feature ran autonomously per standing instruction; decisions are
recorded in `architecture/node-editing.md` (options + rationale per topic).

### Deviations from plan / architecture (node-editing)

- **Self-rename bug caught by the gate tests**: the first
  `rename_search_term` implementation deleted a term renamed to itself (the
  merge branch removed the "old" slot). Fixed with an explicit `old != new`
  guard; the architecture text ("merge on collision") now implicitly means
  *distinct* titles.
- **`pane_bindings_only_match_their_own_pane` (help-modal suite) updated**:
  it asserted plain `d` is unbound in the library — now it is
  `LibraryDeleteNode` by design; the test's queue-only example key moved to
  `c`.
- **`delete_library_node` also maps `InvalidInput` → `invalid_argument`**
  although no provider raises it for delete today — keeps the error contract
  uniform across the three node-mutation rpcs.
- **End-to-end check ran at the provider layer** (as with search): no
  interactive terminal/audio device in this environment; the gRPC handler
  and TUI layers above it are covered by unit tests and review.
- **Environment note**: builds/tests again ran with a session-local
  `CARGO_TARGET_DIR` (owner-built artifacts in `target/`); no repo change.

## search (2026-07-20)

Built per `plan/search.md`: `%` inside `/tidal/search` opens a one-line input;
the term becomes a persistent (per-process) tree node holding Tidal search
results — 20 tracks queueable in place, plus artist/album results as canonical
`/tidal/artists/...` children. Creatable nodes carry an `is_creatable` flag
end-to-end (proto → provider → TUI marker `[%]` + pane hint). All 48 workspace
tests green; every gate in `quality/search.md` checked. Verified against the
live Tidal API: payload shapes match the existing models (probe kept as the
ignored `probe_search_shapes` test), and a full create→list→resolve-URL round
trip succeeded (`beatles` → 20 tracks / 40 children, idempotent, playable
stream URL from a search-track path).

The whole feature ran autonomously on user instruction; decisions were taken
without mid-stage confirmation and recorded in `architecture/search.md`
(options + decision per topic).

### Deviations from plan / architecture (search)

- **`Library::update` now concatenates tracks and children** (tracks first).
  The old code showed tracks *instead of* children, which would have hidden
  the artist/album results on term nodes — architecture assumed both would
  render. Existing nodes are unaffected (they only ever carry one kind).
- **Search categories degrade independently**: a failing category logs and
  contributes nothing; only all three failing is a `FetchError`. The plan
  did not specify partial-failure behavior.
- **`get_lib_node` no longer requires a user id up front** — the gate moved
  into the favorites arms (planned), which also means `create_lib_node`
  validation works fully offline (used by the new unit tests).
- **End-to-end check ran at the provider layer** (temporary ignored test,
  removed after passing) rather than driving the full TUI + server — no
  interactive terminal/audio device in this environment. The gRPC handler and
  TUI layers above it are covered by unit tests and review.
- **Environment note**: `target/` contains owner-built artifacts not writable
  by this agent's user; builds/tests ran with a session-local
  `CARGO_TARGET_DIR`. No repo change involved.

## help-modal (2026-07-20)

Built per `plan/help-modal.md`: `app/bindings.rs` (declarative
`BINDINGS` table + `lookup` + `key_label`), `app/help.rs` (overlay), the
`App::dispatch`/`DispatchResult` seam, and the rewired event loop in
`main.rs`. All 20 tests pass; every gate in `quality/help-modal.md` checked.

### Deviations from plan / architecture (help-modal)

- **Two-column modal layout.** The architecture assumed a single-column list;
  the full table is ~50 rows and would not fit even a 100×40 frame. The modal
  renders Global in the left column and Library + Queue stacked in the right
  column, with the close keys as a footer line (`Close help: ?, Esc, q`)
  derived from the `Scope::Help` bindings instead of a fourth listed group.
  The open question "scroll vs truncate" stays resolved as truncate — but
  after the column split the content fits ~34×94, so truncation only kicks in
  on genuinely small terminals.
- **`Scope` derives `Hash`** (not in the stub) so the chord-uniqueness test
  can use a `HashSet`.
- **`QueueInsertHere` description reworded** to "Insert library selection
  after this track": `crabidy-server`'s `insert_tracks` splices at
  `position + 1`. Same check confirmed the planned "Queue selection after
  current track" wording for `LibraryQueueNext`.
- **`main.rs`** passes `tx` to `App::new` without the now-unneeded clone; the
  `KeyCode`/`KeyModifiers`/`UiFocus`/`StatefulList` imports moved out with the
  old match.