fix: add invite button, voice join dedup, voice panel immediate render

web/src/components/VoiceChannel.tsx

@@ -15,12 +15,20 @@ export function VoiceChannel({ channelId, channelName }: VoiceChannelProps) {
 
   const handleClick = () => {
     if (!isActive) {
-      joinVoice(channelId, channelName);
+      console.log("[VoiceChannel] joining voice:", channelId, channelName);
+      joinVoice(channelId, channelName).catch((err) => {
+        console.error("[VoiceChannel] joinVoice failed:", err);
+      });
     }
   };
 
+  const error = useVoiceStore((state) => state.error);
+
   return (
     <div className="mb-0.5">
+      {error && (
+        <div className="px-2 py-0.5 text-gb-red text-xxs">! {error}</div>
+      )}
       <button
         onClick={handleClick}
         className={`w-full text-left px-2 py-1 rounded-sm flex items-center gap-2 ${