Plex API returns Directory entries without type field, causing
TypeError crash in fromJson. Made fields nullable and migrated
callers to use mediaType enum and displayTitle getter instead
of raw string access.
Catch COMMAND_FAILED/NOT_INITIALIZED in PlayerNative.seek() and
PlayerAndroid.seek() directly, preventing unhandled PlatformException
crashes on macOS app resume. Remove the ~200-line
_PendingSeekCoordinator system and revert all callsites to direct
player.seek(clampSeekPosition(...)). Keep seekable property/stream
and media controls gating. Add ExoPlayer seekable emission.
edde746