Seek-back past the retained tail reuses the existing seek-beyond-buffer
Range path (per-path resolver). A failed refill now halts the scheduler
into a paused-but-loaded state (AC6) instead of a silent false end.
Shared scheduler fill signal (forward water-marks + hard byte cap) pauses
the C# read loop above high-water and, for Opus, stops the demux/decode
feed so WebCodecs queues stay near-empty. Routes through the existing
cancellation discipline; releases the latch on clear/seek.
Add StateChanged multicast event to IPlayerService so AudioPlayerBar and TracksView
re-render themselves without relying on the IsFixed cascade re-render path. Clear
_selectedTrack in TracksView when IsLoaded drops (stop, unload, end-of-track). Set
IsLoaded=false in OnPlaybackEndCallback so end-of-track triggers the same clear path.
Add JS-module readiness probe in AudioInteropService; delete dead TS and buffered C#
path; consolidate GetPlayIcon/FormatTime helpers; fix misleading minimize dock icon.
daniel-c-harvey