fix(realtime): noindex the socket server's 404 responses

The sockets.* hostnames are served by this server and return a plain JSON
404, which Google Search Console reports as crawl errors. Mark unmatched
routes noindex so crawlers drop the hostnames instead of retrying them.

Author: waleedlatif1

apps/realtime/src/routes/http.test.ts

@@ -0,0 +1,44 @@
+import type { IncomingMessage, ServerResponse } from 'http'
+import { describe, expect, it, vi } from 'vitest'
+import type { IRoomManager } from '@/rooms'
+import { createHttpHandler } from '@/routes/http'
+
+function createMocks(req: Partial<IncomingMessage>) {
+  const writeHead = vi.fn()
+  const end = vi.fn()
+  const logger = { info: vi.fn(), error: vi.fn(), debug: vi.fn(), warn: vi.fn() }
+  const roomManager = {
+    getTotalActiveConnections: vi.fn().mockResolvedValue(0),
+    isReady: vi.fn().mockReturnValue(true),
+  } as unknown as IRoomManager
+
+  return {
+    handler: createHttpHandler(roomManager, logger),
+    req: { headers: {}, ...req } as IncomingMessage,
+    res: { writeHead, end } as unknown as ServerResponse,
+    writeHead,
+    end,
+  }
+}
+
+describe('createHttpHandler', () => {
+  it('marks unmatched routes noindex so crawlers drop the socket hostnames', async () => {
+    const { handler, req, res, writeHead, end } = createMocks({ method: 'GET', url: '/' })
+
+    await handler(req, res)
+
+    expect(writeHead).toHaveBeenCalledWith(404, {
+      'Content-Type': 'application/json',
+      'X-Robots-Tag': 'noindex, nofollow',
+    })
+    expect(end).toHaveBeenCalledWith(JSON.stringify({ error: 'Not found' }))
+  })
+
+  it('does not mark the health check noindex', async () => {
+    const { handler, req, res, writeHead } = createMocks({ method: 'GET', url: '/health' })
+
+    await handler(req, res)
+
+    expect(writeHead).toHaveBeenCalledWith(200, { 'Content-Type': 'application/json' })
+  })
+})

apps/realtime/src/routes/http.ts

@@ -150,7 +150,10 @@ export function createHttpHandler(roomManager: IRoomManager, logger: Logger) {
       return
     }
 
-    res.writeHead(404, { 'Content-Type': 'application/json' })
+    res.writeHead(404, {
+      'Content-Type': 'application/json',
+      'X-Robots-Tag': 'noindex, nofollow',
+    })
     res.end(JSON.stringify({ error: 'Not found' }))
   }
 }