Scene-only playlists: playSilence keeps a live audio input running

A playlist made only of ✨ Intermezzo scenes is the visuals-only sequencer
(effects/text/images on a timeline, chained and looping with repeat), but
playSilence tore down the live input source, so effects stopped reacting to
the DJ's real music. Now only file/track audio is silenced; a mic/line/
BlackHole input keeps feeding the analyser through every scene.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

src/control.html

@@ -71,7 +71,7 @@
         <label>Playlist <span id="playlist-count">0 brani</span></label>
         <div class="row">
           <button id="btn-add-tracks">➕ Aggiungi brani/video</button>
-          <button id="btn-add-interlude">✨ Intermezzo effetti</button>
+          <button id="btn-add-interlude" title="Scena visiva senza brano: effetti/testi/immagini a tempo per la durata scelta. Una playlist può essere fatta SOLO di scene (musica dal vivo via Input live)">✨ Intermezzo effetti</button>
           <button id="btn-clear-playlist">🗑 Svuota</button>
           <label class="chk"><input type="checkbox" id="repeat-playlist" /> Ripeti</label>
         </div>

src/output.js

@@ -433,11 +433,13 @@ djv.onControl(async (m) => {
       } catch (e) { djv.report({ type: 'error', message: e.message }); }
       break;
     case 'playSilence':
-      // Visual-only interlude: stop audio + hide the video, keep visuals going.
+      // Visual-only interlude: stop track audio + hide the video, keep visuals
+      // going. A LIVE input (mic/line/BlackHole) is left running: a playlist
+      // made only of scenes must stay audio-reactive to the DJ's real music.
       try {
         trackVideo.pause(); trackVideo.classList.remove('show');
         audio.onEnded = null;
-        audio.silence();
+        if (audio.mode !== 'input') audio.silence();
         hideHint();
         djv.report({ type: 'playState', playing: true });
       } catch (e) { djv.report({ type: 'error', message: e.message }); }