MPD and Scene fixes + twitch-bot cleanup

scripts/loading.sh

@@ -160,8 +160,7 @@ echo "  ✓ wrote $JS"
 # the id is already resolved by the search step above.
 SET_CHANNEL="$OBS_DIR/twitch-bot/set-channel.py"
 if (( have_twitch )) && [[ -x "$SET_CHANNEL" && -n "$game_id" ]]; then
-  twitch_title="$game"
-  [[ -n "$subtitle" ]] && twitch_title="$game — $subtitle"
+  twitch_title="${subtitle:-$game}"
   echo
   if ! "$SET_CHANNEL" --game-id "$game_id" "$twitch_title"; then
     echo "  ! Twitch sync failed (manifest still saved) — fix and re-run if needed" >&2