Run the conformance gate against knowledge

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What to build

knowledge runs the conformance gate against its own booted application.

This service had the least honest spec in the estate before this programme, so it is also where conformance fuzzing has the most to find.

Acceptance criteria

• Read-only operations are fuzzed on every pull request and the gate joins the pipeline aggregator
• The undeclared-status-code check is active
• The scheduled full run covers mutations against an isolated database
• Confirmed to fail against a deliberately non-conforming build

Blocked by

• Reusable Schemathesis conformance workflow
• Adopt the ProblemDetail customizer and re-export the spec