Add End-to-End Test for Orchestration Workflow

[ananos]

We currently lack an end-to-end (E2E) test to validate that all components of MLSysOps work together. This will ensure the orchestrator, runtime, agents, and any required infrastructure are correctly integrated.

Details

We should:

• Create a sample manifest that runs a simple multi-step pipeline.
• Write an E2E test script (e.g., in tests/e2e/test_simple_pipeline.py) that:
  • Brings up necessary services (e.g., Redis, API).
  • Submits the manifest.
  • Polls for job status until completion.
  • Validates output or success condition.

This helps catch integration issues and regressions early.