feat: require repo-scoped verification before Oz results

[oz-for-oss]

Closes #439

Summary

• Add shared repo-scoped verification instructions for webhook-dispatched Oz prompts.
• Require review, implementation, and PR-comment response agents to verify the webhook repository/ref before final artifacts and disclose command pass/fail/skipped status.
• Carry PR head repository/SHA metadata into review prompts so verification can target the actual PR head.
• Add prompt tests covering multiple repository names to confirm the behavior is repo-agnostic.

Validation

• python3 -m compileall /workspace/oz-for-oss/core /workspace/oz-for-oss/tests
• git -C /workspace/oz-for-oss --no-pager diff --check

Notes

• Full unittest/pytest execution was blocked in this sandbox because PyGithub is not installed and Python lacks both pip and ensurepip to install repository requirements.

[captainsafia]

@oz-agent One more tweak.

[oz-for-oss]

@captainsafia

I'm working on changes requested in this PR (responding to a PR review body).

You can view the conversation on Warp.

I pushed changes to this PR based on the comment.

Replied to and attempted to resolve 1 review comment that this run addressed.

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[oz-for-oss]

@captainsafia

I'm working on changes requested in this PR (responding to a PR review body).

You can view the conversation on Warp.

I pushed changes to this PR based on the comment.

Replied to and attempted to resolve 1 review comment that this run addressed.

Next steps:

• Review the changes pushed to this PR.
• Follow up with another comment if further adjustments are needed.

Powered by Oz