feat(rule): source-before-shape — edit-time reuse/scope discipline + capability-reuse-auditor

[artyhoo]

What

Ships source-before-shape — an edit-time discipline that catches two recurring AI-laziness failures at authoring time, closing a recursive-self-application gap in the project's own operating rules.

Origin (2026-07-02, operator-confirmed cross-session recurrence = the promotion trigger):

1. BFR-reinvention — PR feat(skill): night-mode — reusable autonomous-overnight orchestration protocol #858 shipped .claude/skills/night-mode/SKILL.md re-describing the executor+dual-reviewer loop SSOT chore(skills+agents): cleanup batch from 2026-05-16 skills+agents audit #64 already owns. Its Prior-art: trailer correctly said "ADAPT chore(skills+agents): cleanup batch from 2026-05-16 skills+agents audit #64" while the body re-described the loop — and it passed principle 11 F1, which checks trailer presence, not reuse substance. #parallel-evolution-creep + #consult-as-trailer-not-input.
2. scope-from-memory — a launch prompt scoped to "implement D1" from recall when spec §9 defines the chain D1 → B. #claim-from-memory-not-source.

Both disciplines already existed (build-first-reuse-default.md §4, phase-research-coverage.md §1.11) but were delivered always-on / path-scoped-to-research-files — neither fired at the authoring moment. No earliest-reachable channel caught either; the human was the de-facto gate, twice. This adds the action-scoped (edit-time) delivery those parents lacked.

How (judgment → injection, not a gate)

• Layer A — .claude/rules/source-before-shape.md carries <!-- globs: -->/<!-- inject: --> markers → the existing inject-matching-rule.sh surfaces the reminder at edit-time on .claude/skills/**, agents/**, .claude/orchestrator-prompts/**. REUSE of the injector, zero new engine. Honestly disclosed limitation (§3): Layer A is once-per-session → a routine skill/agent edit earlier in the session "spends" it — a best-effort first-touch nudge, not a reliable gate (it would not have fired on its own origin incident feat(skill): night-mode — reusable autonomous-overnight orchestration protocol #858).
• Layer B — agents/capability-reuse-auditor.md, an AI-agnostic overlap + trailer↔body verdict-consistency auditor (no-paid-llm-in-ci), doing the semantic pass F1 structurally cannot. Run before handoff.

Also: SSOT #189 (ADAPT, records the 6-item BFR-consult); principle 09 REQUIRED_HEADER_DOCS +2; install.sh SHIPPED_DOCS +1 (agent shipped to consumers) + regenerated byte-identical baselines; AGENTS.md portable rule-index +1; research-patch Resolution section.

Testing

• npx vitest run packages/core/principles/ → 275/275 (incl. 09 sentinels, 11 F1 via SSOT docs(planning): guard-liveness-gate research-patch #189, 21 rules-autoload).
• bash tests/install-sh/byte-identical.test.sh → 8/8 stack×mode byte-identical + shellcheck clean (baselines regenerated: +1 line each, the shipped agent).
• Injection dogfooded live on all three globs; packages/core/** confirmed excluded.
• Independent 3-lens Workflow review (top-down + bottom-up approve; one adversarial revise applied — the spent-before-creation disclosure asymmetry).
• Pre-existing/out-of-scope (identical on base, not this diff): check-rule-globs.sh (consumer-side ESLint boundary, skipped in maintainer repo) and layer-units.test.sh ×2 (macOS dry-run source failed).

§1.7 Forward-check applied

Complies with each active layer. no-paid-llm-in-ci — Layer A is deterministic bash on the existing hook; Layer B is an AI-agnostic sub-agent (agents/capability-reuse-auditor.md:14 states no API call). build-first-reuse-default — REUSE verdict; the 6-item BFR-consult ran DeepWiki + WebSearch ≥3 phrasings, recorded at docs/meta-factory/prior-art-evaluations.md:262 (SSOT #189: code-clone tools REJECT on T16 problem-class miss, CodeAnt REJECT-as-gate, CyberEvolver/AlignEvoSkill ADOPT-VOCABULARY, Superpowers writing-skills REFERENCE) — not asserted from memory. rule-enforcement-channel-selection — detectability axis → injection not gate (.claude/rules/source-before-shape.md:42). doc-authority-hierarchy — both new files carry headers and are registered at packages/core/principles/09-doc-authority-hierarchy.ts:54. language-discipline — machinery English-only (agents/capability-reuse-auditor.md:1).

§1.7 Backward-check applied

Complete sweep of the scoped surfaces. Parent-rule integrity — source-before-shape.md does not edit or supersede build-first-reuse-default.md §4 or phase-research-coverage.md §1.11 (subordinate delivery layer; Artifact Ownership Contract respected — .claude/rules/source-before-shape.md:15). Install consistency — the shipped agent is enforced end-to-end: header (packages/core/principles/09-doc-authority-hierarchy.ts:132), install list (install.sh:122), byte-identical baseline (tests/install-sh/baselines/react-next/greenfield.fingerprint:12), lockstep sentinel bumps (packages/core/principles/09-doc-authority-hierarchy.test.ts:93). Self-application (T15) — the rule was authored source-before-shape: the SSOT #189 consult drove its shape, and its own Prior-art provenance (REUSE + ADAPT) is true of the body, not a re-description. Falsifier — wrong if a 3rd occurrence exposes a structural trailer↔body signature a deterministic gate would catch, flipping the promotion target from injection to a narrow gate.