fix: backend and discord-gateway improvements

- Update shared database schema
- Add shared utils
- Refactor backend middleware, auth routes, and dashboard repository
- Improve media analysis client with better error handling
- Fix searxng search URL construction
- Update URL fetcher for robustness

Co-authored-by: workflow agents

services/backend/src/modules/auth/auth.routes.ts

@@ -3,18 +3,22 @@ import { createChildLogger } from "@bete/shared/logger";
 import type { Request, Response, Router } from "express";
 import express from "express";
 import { config } from "../../shared/config/index.js";
-import { asyncHandler } from "../../shared/middlewares/index.js";
+import { asyncHandler, rateLimit } from "../../shared/middlewares/index.js";
 
 const logger = createChildLogger("auth.routes");
 
 const adminPassword = config.ADMIN_PASSWORD || "admin";
 
+// Rate limit: max 10 login attempts per IP per 15 minutes
+const loginRateLimit = rateLimit({ windowMs: 15 * 60 * 1000, max: 10 });
+
 export function createAuthRouter(): Router {
   const router = express.Router();
 
   // POST /api/auth/login
   router.post(
     "/auth/login",
+    loginRateLimit,
     asyncHandler(async (req: Request, res: Response) => {
       const { password } = req.body as { password?: string };
 

services/backend/src/modules/dashboard/dashboard.repository.ts

@@ -43,9 +43,10 @@ export class DashboardRepository {
     // Top channels by message count
     const topChannels = await pool.query(`
       SELECT channel_id,
-             (metadata::jsonb -> 'channel' ->> 'channelName') AS channel_name,
+             COALESCE(NULLIF((metadata::jsonb -> 'channel' ->> 'channelName'), ''), channel_id) AS channel_name,
              COUNT(*)::int AS message_count
       FROM messages
+      WHERE metadata IS NOT NULL AND metadata != ''
       GROUP BY channel_id, (metadata::jsonb -> 'channel' ->> 'channelName')
       ORDER BY COUNT(*) DESC
       LIMIT 10