`LangGraph Toolbox` local invoke fails with 500: `TOOLBOX_ENDPOINT` is required but not set

Description:
When executing Scenario 3: LangGraph Toolbox (Responses), the azd ai agent run started successfully locally, but executing the local invocation command azd ai agent invoke --local --protocol responses "What tools do you have?" failed, with the CLI returning agent failed (server_error): An internal server error occurred. See the image below for details:

Steps to Reproduce:

1. mkdir langgraph-toolbox and cd langgraph-toolbox
2. Run azd ai agent init --manifest "https://github.com/microsoft-foundry/foundry-samples/blob/main/samples/python/hosted-agents/bring-your-own/responses/langgraph-toolbox/agent.manifest.yaml" and select location northcentralus.
3. Run azd up.
4. Run azd ai agent run.
5. From a second terminal, run azd ai agent invoke --local --protocol responses "What tools do you have?".

Environment:

• Azd version: azd version 1.24.2-daily.6223381 (commit 7d52038731150e12a5f12aadbfcb09d7413ed0f5) (daily).
• AI Agent Extension version: 0.1.28-preview
• Manifest URL: https://github.com/microsoft-foundry/foundry-samples/blob/main/samples/python/hosted-agents/bring-your-own/responses/langgraph-toolbox/agent.manifest.yaml
• OS: Windows
• Location: northcentralus.

Expected Behavior:
Local invoke can succeed.

@JeffreyCA and @rajeshkamal5050 for notification.