Allow commits to skip Claude review via a head-commit marker

[jonathangreen]

Summary

Adds a way to skip the shared claude-review workflow for a given push, without disabling it on the repo.

Include [skip claude] (or [skip-claude], [claude skip], [claude-skip]) anywhere in the PR's most recent commit message and the review step is skipped. The match is case-insensitive and only the head commit is checked, so pushing a later commit without the marker re-enables review on the next run.

How it works

• Checkout now uses fetch-depth: 2 so the PR head commit (not just the default merge commit) is reachable locally.
• A new step reads the head commit message with git log and sets a skip output when the marker is present.
• The Run Claude Code review step is gated on that output.

README updated to document the marker.

[claude]

Claude finished @jonathangreen's task in 2m 37s —— View job

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Code Review

• Gather context (workflow, README, self-review workflow, invocation surface)
• Verify fetch-depth: 2 reaches the PR head commit
• Validate skip-marker regex against documented markers
• Check injection/security of head.sha interpolation
• Confirm gating correctness and no regression to the review action

Summary

This is a clean, well-scoped change. The fetch-depth: 2 reasoning is correct: actions/checkout checks out the refs/pull/N/merge commit by default on pull_request events, and that merge commit's two parents are the base tip and github.event.pull_request.head.sha — so depth 2 makes the head commit reachable for the local git log read, with no gh api call. The regex \[(skip[ -]claude|claude[ -]skip)\] matches all four documented markers case-insensitively, the head.sha interpolation is a hex SHA so there's no shell-injection surface, and gating the review step on steps.skip_check.outputs.skip != 'true' is correct (and fails closed). The review action reads diffs via gh pr diff rather than local history, so the shallow checkout introduces no regression. The README accurately documents the head-commit-only, case-insensitive behavior. I found no issues that meet the bug-flagging bar and nothing actionable to raise beyond that.

[tdilauro]

LGTM! 🚫🤖