[E09] Reference data source schema

[IanMayo]

Epic

Part of E09: Provenance Graph

Problem

Tool calculations may depend on values drawn from authoritative reference sources outside the Debrief session (e.g. vessel draft from Lloyds Register). There is currently no schema to represent these external references, their captured values, or their currency status.

Proposed Solution

Add LinkML models for:

• Reference source types (web-page, rest-api, local-file, other-session)
• Currency states (current, changed, unavailable, source-structure-changed, unchecked)
• Captured value record (source URI, selector expression, value at capture, timestamp of last fetch)
• Integration with existing Analysis Log Entry schema

Generate Pydantic and TypeScript types from the LinkML models.

Success Criteria

• LinkML schema defines all reference source types and currency states from the spec
• Generated Pydantic models pass validation with representative test fixtures
• Generated TypeScript types are available in @debrief/schemas
• Schema adherence tests pass (golden fixtures, round-trip)

Dependencies

None

Complexity

Medium