feat: replace hourglass emoji with animated SVG spinner in generating state

scraper/internal/server/ui.go

@@ -2596,7 +2596,7 @@ const chapterTmpl = `
   }
 
   function setGenerating() {
-    setPlayIcon('\u231B');
+    setPlayIcon('<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24" width="18" height="18" fill="none" stroke="currentColor" stroke-width="2.5" stroke-linecap="round"><circle cx="12" cy="12" r="9" stroke-opacity="0.25"/><path d="M12 3a9 9 0 0 1 9 9" style="animation:tts-spin 0.8s linear infinite"><animateTransform attributeName="transform" type="rotate" from="0 12 12" to="360 12 12" dur="0.8s" repeatCount="indefinite"/></path></svg>');
     playerPlayBtn.disabled = true;
     voiceSel.disabled = true; speedBtns.forEach(function(b){b.disabled=true;});
     setBadge(playerStateBadge, 'generating');