AIP-20: Build create-review-worktree skill

[jodavis-claude]

Work item

AIP-20: Build create-review-worktree, a skill that, given a resolved PR reference (from resolve-pr-reference's JSON output), stands up an isolated working copy checked out to that PR's head — an EnterWorktree worktree for a same-repo PR, a git worktree add from a sibling clone or a scratch gh repo clone for a cross-repo PR — so every later Code Review Helper deliverable can operate on the PR's code without touching the reviewer's own checkout.

Changes

• plugins/dev-team/skills/create-review-worktree/SKILL.md (new) — the skill itself. Classifies which isolation mechanism a resolved PR needs, then either (a) same-repo: calls the native EnterWorktree tool, runs gh pr checkout <number> -R <owner>/<repo>, and returns isolation_kind: enterworktree, or (b) cross-repo: delegates to the script's finish-cross-repo command, returning isolation_kind: sibling-worktree or isolation_kind: scratch-clone. Documents an explicit return contract (isolation_kind, worktree_path, head_ref) since the spec's prose didn't fix one.
• plugins/dev-team/skills/create-review-worktree/scripts/create_review_worktree.py (new) — deterministic classification and cross-repo execution logic: parse_owner_repo, get_current_repo, get_repo_root, sibling_matches, classify_isolation, finish_cross_repo, and a main() CLI (classify / finish-cross-repo subcommands, JSON in, JSON out).
• plugins/dev-team/skills/create-review-worktree/scripts/test_create_review_worktree.py (new) — 35 pytest tests covering every deterministic branch, including one real (non-mocked) local git integration test for the sibling-worktree path.

Design decisions

• Split a testable script out of the Orchestrator: classify_isolation/finish_cross_repo get full branch-coverage pytest (mirroring decide_cleanup_action.py's precedent), while the untestable EnterWorktree call stays as thin, manually-verified SKILL.md prose.
• Sibling-directory match is verified by comparing the sibling's own git remote get-url origin against the target owner/repo, case-insensitively — resolves an ambiguity the spec left open.
• git worktree add / gh repo clone / gh pr checkout failures propagate as RuntimeError with the underlying stderr — no structured failure taxonomy invented for this component.
• Both cross-repo mechanisms (sibling-worktree, scratch-clone) share the same target directory naming convention: .claude/worktrees/review-<owner>-<repo>-<number>/.
• No Gherkin/E2E scenarios were written — no .feature/Gherkin harness exists anywhere in this repo (confirmed via search), so per missing-test-harness none was invented. The real-git integration test is the closest existing analog for exercising the Orchestrator's primary wiring end-to-end.

Testing completed

• plugins/dev-team/skills/create-review-worktree/scripts/test_create_review_worktree.py: 35 unit/integration tests, all passing (python3 -m pytest test_create_review_worktree.py -q → 35 passed).
• Repo build/test validation scripts run clean (see linked build log in workflow context).

[jodavis-claude]

First-pass review of AIP-20 (create-review-worktree). Exit criteria are met and the deterministic classification/cross-repo logic is thoroughly tested (35 passing pytest tests, including one real non-mocked git integration test for the sibling-worktree path). One correctness/fault-tolerance issue found in the sibling-worktree branch handling (inline comment below) that I'd like addressed before sign-off; one minor documentation clarity note as well.

[jodavis-claude]

Sign-off review for AIP-20 (create-review-worktree).

Prior review threads (2/2 resolved):

1. Stray branch left in sibling clone (Priority 2, correctness/fault-tolerance) — fixed in commit c75849a. finish_cross_repo()'s sibling-worktree path now uses git worktree add --detach <target_dir> HEAD instead of -b <branch>, so no orphaned review-<owner>-<repo>-<number> branch is left behind in the sibling clone, and a second review of the same PR no longer fails with "branch already exists". Verified: new regression test test_finish_cross_repo_sibling_worktree_does_not_leave_a_stray_branch_in_sibling_clone is a real (non-mocked) git integration test that fails against the pre-fix code and passes against the fix. Thread resolved.
2. SKILL.md "skip step 3" wording ambiguity (Priority 5, documentation clarity) — fixed in commit 67f3921. Reworded to "The Cross-repo section below does not apply to the same-repo path," matching the reviewer's suggested wording and removing the ambiguity with step 2's own internal item 3. Thread resolved.

New issues in modified files (commits c75849a, 67f3921): none found. Reviewed create_review_worktree.py's changed lines, SKILL.md's changed line, and the new test's mocking pattern (matches the existing _passthrough_except_gh real-git precedent already used by the sibling class in this file, not a new deviation).

Verification: all 36 tests pass (python3 -m pytest test_create_review_worktree.py -q → 36 passed).

Approved — no further changes requested.