fix: surface voice channel full errors for join-voice-listen IPC

Return UI error toast instead of ipc dispatch failed when voice
channel is at capacity for listen-only joins.

Co-authored-by: Cursor <[email protected]>

index.js

@@ -458,13 +458,29 @@ async function dispatchUiMessage (platform, msg, hooks = {}) {
     return true
   }
   if (t === 'join-voice') {
+    try {
       await platform.joinVoiceChannel(msg.channelId)
       pushState()
+    } catch (err) {
+      if (/voice channel is full/i.test(err?.message || '')) {
+        send({ type: 'error', message: err.message })
+        return true
+      }
+      throw err
+    }
     return true
   }
   if (t === 'join-voice-listen') {
+    try {
       await platform.joinVoiceListenOnly(msg.channelId)
       pushState()
+    } catch (err) {
+      if (/voice channel is full/i.test(err?.message || '')) {
+        send({ type: 'error', message: err.message })
+        return true
+      }
+      throw err
+    }
     return true
   }
   if (t === 'leave-voice') {