Add one explicit action-order rule in Additional Guidance for when
rule #6 applies to explicitly unresolved uncertainty:
1. First check whether an existing unresolved node already represents
the same uncertainty.
2. If so, update/refine that existing structure rather than creating
a duplicate.
3. If no such node exists, add a new unknown that directly represents
the unresolved uncertainty.
4. Do not use an edge alone to represent a previously unrepresented
uncertainty.
14 focused prompt tests verify: existing-first ordering, reuse path,
fallback-to-add, related-node-insufficient, edge-only-prohibited,
possibleInference separation, resolution path preserved, duplicate
contract preserved, scope uncertainty-only, fidelity/traceability
preserved, noop validator untouched, no semantic classifier added.
- Add answerMeaning schema with supportCategory and resolutionGuidance enums
- Add pre-mutation guard that validates proposal alignment with answerMeaning
- Update prompt builder to instruct the model on answerMeaning contract
- Add tests for schema, guard logic, parsing defaults, and regression cases A-D