HyprTile wallpaper now-playing / MPRIS changes
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- Added direct session D-Bus/MPRIS fallback to hyprtile-wallpaperd.
- No playerctl helper is used.
- Reads PlaybackStatus plus xesam:artist/xesam:title from org.mpris.MediaPlayer2.*.
- F2 keeps priority while its state is playing or paused.
- F2 stopped, idle, unavailable, or not running no longer exposes stale track metadata.
- When F2 is inactive, a currently Playing MPRIS source can supply Artist — Title.
- If neither source has an active/current track, the now-playing shader texture is hidden.
- Build now links hyprtile-wallpaperd with libsystemd for sd-bus.
