feat: notify other participant via gateway when a conversation is deleted

src/messages/messages.controller.ts

@@ -298,7 +298,22 @@ export class MessagesController {
     @Param('id') conversationId: string,
     @CurrentUser('id') userId: string,
   ) {
-    return this.messagesService.deleteConversation(conversationId, userId);
+    // Get the other party before deletion so we can notify them
+    const participants = await this.messagesService.getConversationParticipants(conversationId);
+    const result = await this.messagesService.deleteConversation(conversationId, userId);
+
+    // Notify the other party so their client removes the stale conversation
+    if (participants) {
+      const otherUserId = userId === participants.userId
+        ? participants.agentUserId
+        : participants.userId;
+      this.messagesGateway.sendToUser(otherUserId, 'conversation_deleted', {
+        conversationId,
+        deletedBy: userId,
+      });
+    }
+
+    return result;
   }
 
   // ==========================================