tdd

# tdd Test-first, or it does not ship. Routed to by `/feature` (after spec approval), `/fix`, and `/refactor`. ## Pre-flight Read these, or STOP and surface the gap — never guess a command or a threshold: - `<project-root>/.codearbiter/CONTEXT.md` — the `stage:` frontmatter (the maturity value) and project context. - `<project-root>/.codearbiter/tech-stack.md` — test, coverage, and lint invocations; file layout; mock patterns. - `<project-root>/.codearbiter/coding-standards.md` — style, structure, naming. Required for Phase 3. - `<project-root>/.codearbiter/specs/<slug>.md` — the approved spec, when `/feature` produced one. It is the primary obligation source. - `<project-root>/.codearbiter/security-controls.md` — only when the change touches a security boundary (auth, crypto, secrets, a trust boundary). Optional; absent on most changes. - `<project-root>/.codearbiter/code-map.md` — if present, a coarse concern→path→role map to orient before writing tests and code. Absent is fine — it is read-on-demand, populated by context-creation or commit-gate heal. ## Phase 1 — Obligation scan · gate: BLOCK An **obligation** is one verifiable claim about the change: (a) a unique ID, (b) a source citation, (c) a status. Status moves `OPEN → MAPPED → COVERED`; an obligation Phase 4 cannot tie to a passing test is `MISSING`. "We should test X" is not an obligation. Derive every obligation before any code is written, and record each as `ID · source · OPEN`: - **Spec** — one obligatio...