Bind extension config file hashes in the manifest projection

[gvonnessi]

Summary

• Three auxiliary files drive integrity-significant rendered output — academic/numbering.json (cross-reference numbers), semantic/bibliography.json and semantic/glossary.json (rendered citations/definitions) — yet the manifest referenced each by path only, with no hash. They were in neither the document hash nor the signed manifest projection, so a repackager could renumber, re-cite, or redefine a frozen/signed document while every signature still verified and the document id was unchanged.
• Declare these references as {path, hash} objects and bind their hashes through the manifest projection. The binding is generic: the projector collects every {path, hash} reference declared in an extension config slot — keyed on the shape, not on a field name — into a sorted, deduplicated configFiles set, so a manifest-covering signature now attests each file's content and a newly defined hashed config file is covered without changing the projector. Advisory configuration that is not a file reference is left unbound.
• The normative projection definition (security §9.7/§9.8), the integrity-status disclosures (academic §13, semantic §11, the shared integrity-tier framework), and the academic/semantic config schemas are updated to match. The example loader now verifies each declared config-file hash against the file's bytes.

Re-freeze

• No example document id moves — config slots are outside the document id.
• Both signed manifest projections are byte-unchanged — neither signed example declares a config file, so configFiles is omitted (never emitted empty).

Test plan

• npm test (now also verifies config-file declared hashes against the real files), npm run test:canonicalize.
• New projection KAT vector config-file-references (expected JCS + sha256 independently derived) + a conflicting-hash error vector; check:manifest-projection green and both signed projections unmoved.
• check:manifest-extension-config requires {path,hash} (bare-string and missing-hash rejection vectors).
• Seed-and-revert: a bare-string config → schema gate exit 1; a wrong declared hash → validate:examples exit 1.
• All 19 gates green from a clean npm ci (verified by exit code); npx tsc --noEmit clean; npm audit 0 high.