Use durable room13 tunnel with browser-like UA for github-issues worker

src/room13-worker.ts

@@ -168,7 +168,10 @@ export class GitHubIssuesRoom13WorkerRuntime {
   }
 
   private async request<T = unknown>(method: string, path: string, body?: unknown) {
-    const headers: Record<string, string> = { 'content-type': 'application/json' };
+    const headers: Record<string, string> = {
+      'content-type': 'application/json',
+      'user-agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/123.0.0.0 Safari/537.36',
+    };
     if (this.bearerToken) headers.Authorization = `Bearer ${this.bearerToken}`;
     const response = await fetch(`${this.baseUrl}${path}`, {
       method,