Address adversarial review findings

- evals/README.md, evals/CLAUDE.md: fix uv install command from
  'uv sync --dev' to 'uv sync --extra dev'. Drill's pyproject.toml
  uses [project.optional-dependencies], so --dev is a no-op for
  pytest/ruff/ty; --extra dev is the correct invocation.
- tests/claude-code/run-skill-tests.sh: drop test-requesting-code-review.sh
  from integration_tests array (file deleted earlier in this branch).
- tests/claude-code/README.md: replace test-requesting-code-review.sh
  section with test-worktree-native-preference.sh (the worktree test
  is kept; the code-review test was lifted into drill).
- docs/testing.md, CLAUDE.md: remove "Copilot CLI" from the harness
  list. evals/backends/ has claude*, codex, gemini configs but no
  copilot.yaml, so the claim was unsupported.

Adversarial review credit: reviewer #2 found four legitimate issues
(uv-sync, run-skill-tests stale ref, README stale ref via #1, and
Copilot CLI fabrication); reviewer #1 found two distinct issues
(run-skill-tests + tests/claude-code/README.md). Reviewer #2 wins
this round.

tests/claude-code/run-skill-tests.sh

@@ -79,7 +79,6 @@ tests=(
 # Integration tests (slow, full execution)
 integration_tests=(
     "test-subagent-driven-development-integration.sh"
-    "test-requesting-code-review.sh"
 )
 
 # Add integration tests if requested