fix(room): prevent double-send, log resubscribe errors, dim pending messages

- sendMessage: guard with sendingRef to prevent concurrent in-flight
  sends (was missing — rapid clicks could create duplicate messages)
- resubscribeAll: log at warn level instead of silently swallowing,
  so operators can observe auth expiry or persistent failure patterns
- RoomMessageBubble: apply opacity-60 when isPending or isFailed,
  and hide action toolbar for pending messages (can't react/act on
  unconfirmed messages)

src/components/room/RoomMessageBubble.tsx

@@ -215,6 +215,7 @@ export const RoomMessageBubble = memo(function RoomMessageBubble({
         grouped ? 'py-0.5' : 'py-2',
         !isSystem && 'hover:bg-muted/30',
         isSystem && 'border-l-2 border-amber-500/60 bg-amber-500/5',
+        (isPending || isFailed) && 'opacity-60',
       )}
     >
       {/* Avatar */}
@@ -416,7 +417,7 @@ export const RoomMessageBubble = memo(function RoomMessageBubble({
       )}
 
       {/* Action toolbar - inline icons when wide, collapsed to dropdown when narrow */}
-      {!isEditing && !isRevoked && (
+      {!isEditing && !isRevoked && !isPending && (
         <div className="flex items-start gap-0.5 opacity-0 transition-opacity group-hover:opacity-100">
           {isNarrow ? (
             /* Narrow: all actions in dropdown */

src/contexts/room-context.tsx

@@ -784,10 +784,17 @@ export function RoomProvider({
     [activeRoomId],
   );
 
+  // Guard against double-sending while a previous send is in-flight.
+  // Without this, rapid clicking can queue multiple optimistic messages and
+  // create duplicate sends on the server.
+  const sendingRef = useRef(false);
+
   const sendMessage = useCallback(
     async (content: string, contentType = 'text', inReplyTo?: string) => {
       const client = wsClientRef.current;
       if (!activeRoomId || !client) return;
+      if (sendingRef.current) return;
+      sendingRef.current = true;
 
       // Optimistic update: add message immediately so user sees it instantly
       const optimisticId = `optimistic-${crypto.randomUUID()}`;
@@ -843,6 +850,8 @@ export function RoomProvider({
           ),
         );
         handleRoomError('Send message', err);
+      } finally {
+        sendingRef.current = false;
       }
     },
     [activeRoomId, user],

src/lib/room-ws-client.ts

@@ -916,15 +916,17 @@ export class RoomWsClient {
     for (const roomId of this.subscribedRooms) {
       try {
         await this.request('room.subscribe', { room_id: roomId });
-      } catch {
+      } catch (err) {
-        // ignore
+        // Resubscribe failure is non-fatal — messages still arrive via REST poll.
+        // Log at warn level so operators can observe patterns (e.g. auth expiry).
+        console.warn(`[RoomWs] resubscribe room failed (will retry on next reconnect): ${roomId}`, err);
       }
     }
     for (const projectName of this.subscribedProjects) {
       try {
         await this.request('project.subscribe', { project_name: projectName });
-      } catch {
+      } catch (err) {
-        // ignore
+        console.warn(`[RoomWs] resubscribe project failed (will retry on next reconnect): ${projectName}`, err);
       }
     }
   }