Add error toast on connection failure.

src/app/components/VoiceRoomItem.svelte

@@ -5,6 +5,7 @@
   import SecondaryNavItem from "@lib/components/SecondaryNavItem.svelte"
   import ProfileCircle from "@app/components/ProfileCircle.svelte"
   import RoomName from "@app/components/RoomName.svelte"
+  import {pushToast} from "@app/util/toast"
   import {deriveVoiceParticipants, joinVoiceRoom, currentVoiceSession} from "@app/voice"
 
   interface Props {
@@ -17,7 +18,14 @@
   const participants = deriveVoiceParticipants(url, h)
   const isActive = $derived($currentVoiceSession?.url === url && $currentVoiceSession?.h === h)
 
-  const handleClick = () => joinVoiceRoom(url, h)
+  const handleClick = async () => {
+    try {
+      await joinVoiceRoom(url, h)
+    } catch (e) {
+      const message = e instanceof Error ? e.message : String(e)
+      pushToast({theme: "error", message: `Failed to join voice room: ${message}`})
+    }
+  }
 
   $effect(() => {
     for (const pk of $participants) {