Update AGENTS.md file

packages/backend/convex/globals.d.ts

@@ -5,7 +5,6 @@ declare const process: {
     readonly USESEND_API_KEY?: string;
     readonly USESEND_URL?: string;
     readonly USESEND_FROM_EMAIL?: string;
-    readonly CONVEX_CLOUD_URL?: string;
     readonly [key: string]: string | undefined;
   };
 };