Model library: remembered GLBs with one-click switching

Every loaded model (GLB or converted FBX) is added to 'I miei modelli'
in the Animazioni 3D tab: click a name to switch the dancer instantly
(active one highlighted), x removes it from the list (file untouched).
Persisted in localStorage; the current model is seeded on first run.

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

src/control.html

@@ -167,6 +167,8 @@
         <input type="file" id="glb-input" accept=".glb,.fbx" hidden />
         <div class="hint-mini" id="glb-name">Il modello ruota e balla a tempo di musica nella famiglia “Modello 3D”;
           con la camera lo comandi in “Interattivo Avatar”.</div>
+        <label>I miei modelli</label>
+        <div id="glb-models" class="glb-models"></div>
         <label>Sfondo</label>
         <select id="glb-bg">
           <option value="gradient">Gradiente</option>