feat: support runtime schema registration

[cursor]

Description

Adds a generated registerSchema(name, schema) hook so internal/extension MCP servers can register schemas during startup before schema tools/resources are registered. This keeps runtime schema names in shared SCHEMAS/VALID_SCHEMAS state and prevents the hook from being lost on the next schema sync.

Type of Change

• Bug fix
• New feature
• Refactor
• Documentation
• Other

Checklist

• Tests pass
• Typecheck passes

Verification:

• pnpm test tests/resources/harness-schema.test.ts
• pnpm typecheck
• pnpm build
• pnpm test

  

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[cursor]

Important:

• scripts/sync-schemas.js:133 / generated src/data/schemas/index.ts:42: registerSchema() accepts any object and immediately advertises it via VALID_SCHEMAS. I verified that registering {} succeeds and harness_schema(resource_type='malformed-runtime-test') then returns an empty summary instead of failing loudly. Please validate the expected definitions[name][name] root before mutating the registry, and add a regression test for malformed runtime schemas.

  

_{Sent by Cursor Automation: Sunil On Demand Architecture Review}

[cursor]

registerSchema() currently trusts any object shape. I was able to register {} successfully, which adds the name to VALID_SCHEMAS, and then harness_schema(resource_type=...) returns an empty summary instead of a clear error. Since this repo prefers fail-loudly contracts, please validate the expected definitions[name][name] structure before mutating the registry, and add a negative test alongside the new happy-path cases.