file-placement: exempt the pack -> engine-surface reach the contract mandates

[missingbulb]

A consumer repo waived basics/file-placement for a local pack rule importing the checks helpers:

".claudinite/local/packs/tldr/ci-excludes-claudinite.mjs" — "a pack rule importing the shared
checks engine's helpers is a structural cross-cutting dependency every pack rule takes…"

That is the fourth copy of the same waiver. This repo already carried three near-identical acceptances — packs/, skills/, and .claudinite/local/packs/canon-curation/ — each reasoning that pack check modules share the engine lib by construction.

Why it's the rule, not the repos

Neither end of the reference can move. The pack loader discovers packs at fixed paths (packs/, .claudinite/local/packs/), and the engine is vendored canon a consumer doesn't own to restructure. The distance is fixed by the contract:

	distance
packs/basics/*.mjs → engine/checks/helpers/ (canon home)	5
.claudinite/local/packs/<pack>/*.mjs → .claudinite/shared/engine/… (consumer)	7

Every pack module ever written takes it, in every repo. A waiver each adopter has to write is a rule flagging a constant, so the rule now knows the exemption rather than each project restating it.

Changes

• packs/basics/file-placement.mjs — a third exemption, keyed on the reference rather than the source file (unlike the mandated-location and test-location ones): a pack module reaching the engine surface. The surface is engineSurface() from engine/checks/helpers/module-imports.mjs — the same allow list pack-independence enforces — so "what a pack may import" and "what placement exempts" cannot drift apart. SHARED_SUBDIR handles the consumer-mount prefix.
• packs/basics/skills/file-placement/SKILL.md — documents it as the third exemption, stated portably (a framework that mandates both where extensions live and what they may import) with the corpus instance named. Keeps the same narrowness the other two have.
• .claudinite-checks.json — drops the three acceptances the change makes dead.
• packs-tests/basics/file-placement.test.mjs — the pack test this rule never had (8 cases). Seen failing before the rule change; the three exemption cases fail without it.

Narrowness is pinned by test: a pack reaching into another pack, or deep into its own subtree, is still flagged, and ordinary code reaching into the engine surface is untouched.

Rejected alternative

Raising the distance threshold. It would need ≥8 to cover the consumer case, which guts the rule for everything it's good at.

Verification

• node --test over all CI roots: 814 pass, 0 fail
• check_the_world: 0 blocking, 7 advisory — identical to main. All 7 are pre-existing engine-internal reaches (engine/hooks/ and engine/scheduler/ → engine/checks/helpers/), untouched by this change and never covered by the removed acceptances.

The consumer repo can drop its exception once it baselines.

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Generated by Claude Code