Persistent per-platform mode that plays only the audio track to save
bandwidth and speed up loads. When enabled, stream selection picks the
best audio-only stream (preferred language, codec, bitrate) and never
fetches the video URL; toggling mid-video reloads at the current
position using the quality-switch path (live vid=no toggling is avoided
due to A/V desync).
- Toggle row in the player quality/settings sheet on iOS, macOS and
tvOS, next to lock controls
- New audioMode control button type (red when active) for player
controls and mini player layouts
- Picking a video quality explicitly turns the mode off; audio track
picks keep it on and now work while audio-only is playing
- Stream URL refresh preserves audio-only playback instead of
resurrecting video
- Queue preloads and history entries resolved before a toggle are
discarded so selection re-runs with the current mode
- tvOS player shows the video thumbnail instead of a black screen
during audio-only playback
- PiP button hidden for audio-only streams
Render the macOS control bar button row and top bar from the active
preset's sections via a new MacOSControlsSectionRenderer, replacing the
hardcoded QuickTime-style rows in MacOSControlBar. Add a keepOnTop
button type and macOS-specific button availability lists, and adapt the
player controls settings editors (preset editor, section editor, button
configuration) for macOS.
Also apply the preset font style to the control bar time labels, and
update the built-in macOS Default preset order (queue before transport,
fullscreen at the end), bumping builtInPresetsVersion to 7.
Extract shared TimeInterval.formattedAsTimestamp replacing 8 identical
formatTime/formattedTime implementations across player views. Remove
unused currentTime parameter from GestureSeekPreviewView. Consolidate
duplicated geometry math in MacOSControlBar into seekPreviewPosition().
