Refactor JWT_SECRET handling and add setup warning page

src/index.ts

@@ -3,16 +3,7 @@ import { handleRequest } from './router';
 
 export default {
   async fetch(request: Request, env: Env, ctx: ExecutionContext): Promise<Response> {
-    // Security check: JWT_SECRET must be set
-    if (!env.JWT_SECRET) {
-      return new Response('Server configuration error: JWT_SECRET is not set', { status: 500 });
-    }
-    
-    // Security check: warn if JWT_SECRET is too weak
-    if (env.JWT_SECRET.length < 32) {
-      console.warn('[SECURITY WARNING] JWT_SECRET should be at least 32 characters for adequate security');
-    }
-    
-    return handleRequest(request, env);
+
+  return handleRequest(request, env);
   },
 };