ci: add Bazel RBE lane

[haasonsaas]

Summary

• add Bazel 9/Bzlmod/rules_python wiring for the Mocktopus package and pytest suite
• add a compiled Python requirements lock plus local/remote Bazel Make targets
• add a repo-scoped Bazel RBE workflow gated by BAZEL_RBE_ENABLED and the evalops-mocktopus-rbe runner label
• allow the existing invalid_request example error type in the scenario schema so checked-in examples and tests agree with server behavior

Test plan

• actionlint .github/workflows/ci.yml .github/workflows/bazel-rbe.yml
• PYTHONPATH=src python3 -m pytest -q
• make bazel-check

[cursor]

PR Summary

Medium Risk
Introduces new Bazel/Bzlmod build + dependency locking and a self-hosted GitHub Actions workflow, which can affect CI reliability and build reproducibility. Runtime code change is minimal (schema enum expansion) but build/CI configuration changes are broad.

Overview
Adds a Bazel 9/Bzlmod build setup for the Python package and pytest suite, including MODULE.bazel/lockfile, BUILD.bazel targets, a pinned requirements_lock.txt, and Makefile targets to format/tidy/test locally and via Bazel.

Introduces a new GitHub Actions workflow (bazel-rbe.yml) that runs a Bazel Remote Build Execution smoke test on a labeled self-hosted runner (gated by BAZEL_RBE_ENABLED), plus a helper script to open a GCP IAP tunnel and run Bazel with the remote config.

Updates .gitignore for Bazel outputs and expands the scenario schema in core.py to allow the invalid_request error type.

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[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

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[cursor]

CI workflow missing uv needed by bazel-check

High Severity

The bazel-check Make target depends on requirements-lock, which runs uv pip compile. However, the bazel-rbe.yml workflow never installs uv — it only sets up Go, bazelisk, and buildifier. The existing ci.yml workflow uses astral-sh/setup-uv for this purpose, but that step is absent here. This will cause the make bazel-check step to fail with a command-not-found error every time the workflow runs.

Additional Locations (1)

• Makefile#L27-L28

 

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