test(01-02): add unit tests for scoring functions and taskMetadata passthrough
- Add scoreModel, computeTaskRequirements, scoreEligibleModels, getEligibleModels
describe blocks to model-router.test.ts (27 new tests)
- Add ClassificationResult taskMetadata describe block to complexity-classifier.test.ts
(4 new tests: execute-task populated, hook undefined, plan-slice undefined, extractTaskMetadata export)
- Add getModelTier unknown-default tests verifying standard tier (not heavy) per D-15
- All 42 model-router tests pass, all 32 complexity-classifier tests pass
- All 36 pre-existing capability-router tests continue to pass