ABB: role becomes a closed enum, and the vendor control gets teeth

[mdheller]

#223 shipped three instances of the defect class it was written to close. Found by turning today's Apple-container lens back on our own spec.

1. The vendor-role control never looked at a document

It built one and then never used it:

e = copy.deepcopy(example)
e["role"] = v          # <- assigned, never passed to a validator
if _VENDOR_ROLES_FORBIDDEN.match(v):   # matches the STRING, not the document

So the regex was only ever tested against its own six fixtures. With role: "postgres" in the shipped example, the validator exited 0 and printed OK 6 vendor-named roles caught by the deny list. A control that reports catching what it has not looked at is worse than an absent one — it produces evidence.

2. A deny list cannot prevent the failure that compounds

role was {type: string, minLength: 1}. Vendor names are the obvious slip; the one that actually accumulates is the same role spelled several ways. Measured on macOS 26.3.1 — 627 sandbox containers, extension-point names including:

spelling	count
extension	45
DiagnosticExtension	8
diagnosticextension	5
diagnostic	3
Extension	2

Fifteen years of a freeform role field with no enforced grammar. Past that point the name cannot group anything and a side-channel record has to carry the contract instead. An allowlist forecloses both failures at once, and forecloses them in the schema — the artefact every consumer already validates against, unlike a validator's private regex.

3. conformanceTest pointed at a file that does not exist

conformance/abb-database-vectors.json is not in the repo. format: uri-reference is a syntax check and resolves nothing, so the dangling pointer validated clean — and read as "held to shared vectors" to every consumer that did not go looking.

What changed

• role is a closed enum over the four roles actually in use (prophet-mesh specs/abb-catalog.yaml + the example), never roles we imagine wanting. Adding one is a spec PR — the reviewed gate whose absence produced the five spellings above.
• The deny list is deleted. Its cases now go to the schema as documents: 8 vendor names, 6 case/whitespace variants, 1 invented role — all rejected.
• INVARIANT 1a mutation-tests the enum. Without it, the cases above keep passing if role reverts to a freeform string while some unrelated constraint does the rejecting. Drop the enum ⇒ postgres accepted; restore ⇒ rejected.
• INVARIANT 3 resolves the pointer, with a negative control proving a dangling one is caught. The example's dangling pointer is removed, not backfilled — absence is documented as meaningful, and inventing vectors no implementation runs would be a new paper control.

Verified by probe, not by exit code

document	before	after
`role: postgres"	rc=0, printed OK	rc=1
role: database (case variant)	rc=0	rc=1
dangling conformanceTest	rc=0	rc=1

34 checks. make validate green. No other role field in the repo shares this schema, and an estate-wide scan of prophet-mesh / prophet-platform / Noetica found no ABB role outside the enum.

[Copilot]

Pull request overview

This PR hardens the ArchitecturalBuildingBlock (ABB) contract by moving role validation into the canonical schema (closed enum) and strengthening validator invariants so invalid roles and dangling conformance pointers reliably fail validation.

Changes:

• Converted role from a freeform non-empty string to a closed enum in schemas/ArchitecturalBuildingBlock.json.
• Replaced the prior regex-based vendor-role deny check with schema-backed document mutations plus an enum “mutation test” in tools/validate_architectural_building_block.py.
• Removed the example’s dangling conformanceTest pointer and added validator enforcement that conformanceTest must resolve (or be absent).

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
tools/validate_architectural_building_block.py	Removes ineffective regex deny-list logic; adds schema-backed invariants for enum enforcement and conformanceTest resolution.
schemas/ArchitecturalBuildingBlock.json	Makes role a closed enum and expands documentation around role/conformanceTest semantics.
examples/architectural-building-block.example.json	Drops a dangling conformanceTest pointer from the shipped example.