[P2.5-T14] Precedence rules + skill-verb contract docs in CLAUDE.md

[firatcand]

Forge task ID: P2.5-T14
Phase: 2.5 — Closed-loop workflow control · Type: docs · Owner: backend-dev · Priority: P1 · Estimate: S
Depends on: P2.5-T01
Source: spec/SPEC.md §Skill ↔ verb contract + §Precedence rules

Update CLAUDE.md with:

1. §Precedence rules — the 6-level binding contract (user > SPEC > PRD > phases.yaml > tracker body > attempts)
2. §Skill ↔ verb contract — skills own UX/confirmation; verbs own state machine
3. §Ephemeral ADR workflow — /update-spec --draft → review → flip status: accepted → /update-spec --apply <slug>

Optional lint task: a pre-commit hook that grep-checks new code for forge orchestrate next|suggest-next|session-check|intent-detect references and fails if found.

Acceptance:

• CLAUDE.md sections added: §Precedence rules, §Skill ↔ verb contract, §Ephemeral ADR workflow
• Optional lint hook (commit-time grep for removed verbs) added to .husky/ if husky is in use; otherwise documented in CONTRIBUTING.md