e2e tests to cover UDF failure scenarios

[yhl25]

Parent Issue

Part of #3367 — Remove monitor container and move functionality to numa container

Overview

Add end-to-end tests that exercise UDF crash/failure paths and verify that errors are correctly captured by the numa container, propagated through the daemon server, and visible via the UI server.

Test Scenarios

• UDF container crashes mid-processing — verify numa container stays up and error is recorded
• UDF container restarts multiple times — verify errors accumulate and are queryable
• Daemon server returns correct critical errors after a UDF failure
• UI server displays the errors surfaced by the daemon server

Acceptance Criteria

• e2e test for UDF crash with numa container remaining healthy
• e2e test verifying errors are retrievable via daemon server API
• e2e test verifying errors are visible in the UI
• Tests are integrated into the CI pipeline