Switches the REST endpoints serving the PWA remote control from the
legacy commands::playback::* helpers to their V2 equivalents:
- play_queue_track / play_queue_index / play_album:
commands::playback::play_track -> commands_v2::v2_play_track
- seek: commands::playback::seek -> commands_v2::v2_seek
- set_volume: commands::playback::set_volume -> commands_v2::v2_set_volume
The HTTP contract (paths, methods, payload shapes, response codes,
emit_playback_update side-effects) is unchanged. Behaviour gains the
V2 features that legacy lacked (CMAF cache hits, ALSA hardware
sample-rate guard, manual-offline-mode awareness) because the PWA
remote now flows through the same playback path as the desktop UI.
Drops the `commands` import from this module (now only `commands_v2`
is used) and adds the State acquisitions needed by v2_play_track:
CoreBridgeState, OfflineState, RuntimeManagerState.
cc
vicrodh
2d60f50140