implement

# Test-driven implementation ## Test criteria application When the project explicitly adopts Test-model criteria, use the selectively loaded guidance below for test quality and maintenance. These criteria replace source-local shared test-purpose, case-selection and maintenance criteria for adopted work; retain specialist methods and historical procedures. Actual judgments, evidence applicability and closeout consequences remain with the responsible assessors under the project's review policy. ## Quick operating guide Use this skill to: - implement one approved milestone or isolated request with proof first. Read first: - change-local state when planned; - the current milestone, governing spec, active test spec, recorded review evidence, relevant code/tests, and validation commands. Produce: - tests or proof, implementation, validation evidence, and a code-review handoff. Stop when: - authority, scope, proof, or validation is missing, contradictory, stale, or failing. Do not claim: - review, branch, PR, final-verification, or final-closeout outcomes. Next stage: - code-review. Use full-file or broader-section reading when bounded evidence cannot preserve correctness. ## Review and Closeout application When project authority explicitly adopts Review and Closeout policy, use the packaged application below for shared assessment meaning. It replaces source-local judgment, independence, applicability, concern-disposition and closeout rules in this skill and its conditio...