Two verbs that rewrite what the queue already holds instead of adding to
it: DedupQueue and SortQueue, on the playback loop, for every client.
Client-side was the tempting shortcut and the wrong one — a
client-computed Remove races the resolve stream, and "sorting" as a
Replace of paths re-resolves everything through providers and restarts
playback at the head.
A duplicate is the same provider item id *scoped to its provider* (the
content store keys content the same way, so unscoped ids let two
providers' numeric ids collide), or the whole path when a provider
reports no id. Deliberately not artist+title: identical metadata is
routinely a different recording, and a wrong merge is unrecoverable
queue state. Within a group the playing entry survives, else the
earliest — "keep the first" stops the music whenever the playing copy is
a later one — and the removal itself goes through remove_tracks, so one
code path maintains play_order.
Sorting permutes `tracks` and then treats the play order by mode: with
shuffle off it rebuilds it as the identity with the cursor on the current
track (the sort decides what plays next), with shuffle on it remaps it
through the permutation so the shuffled sequence and the position in it
survive. Five stable strategies (artist→album, album, title, duration,
reverse), keys built once per track, unknown sorting last in both
directions, and UNSPECIFIED refused as InvalidArgument.
DedupQueue answers with a count, alone among the queue verbs: 0 cannot be
recovered from the new snapshot and is what a user needs to hear. It
crosses as a number — the wording is each client's. TUI: `u` and a modal
`S` sort menu whose unclaimed keys are swallowed, plus the count in the
queue pane title. Web: the same keys, clickable menu rows, toolbar
buttons, count in a toast. CLI: `queue dedup` and `queue sort <key>
[--desc]` with the strategy as a ValueEnum.
Full dev-flow: architecture/queue-order.md, quality/queue-order.md,
plan/queue-order.md, plan/summary.md.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
001abcc35c