S4a-2 of the PlexPlayer decomposition. Move three self-contained,
byte-equivalent behaviours into lib/plexPlayerHooks.ts: useWallClock
(15s top-bar clock), useFullscreen (wrapper fs toggle + reactive flag),
and useControlsVisibility (auto-hiding control bar + wake). The ref
mirrors the hooks read (barAutoHide/menuOpen/video-paused) stay in the
component and are passed in, so the timer sees fresh state. No behaviour
change; verified by self-E2E (real HLS playback: clock renders, controls
auto-hide after 3s while playing, wake restores + stays while paused).
peter
c7a69596ad