User Story

As Maya, in order to verify the field mapping between the extracted spec and the source PDF’s AcroForm fields was done correctly and compare how different models handle mapping, I want field-mapping variants to be selectable from Settings → Variants, with mapping-accuracy evaluation.

Preconditions

• #58 (Story 10 variant picker) merged to main

Acceptance Criteria

• New evaluation kind field-mapping scores spec-field → PDF-field matches against reviewed ground-truth mappings on the three fixtures (pardon, I-9, W-9)
• Deterministic scorer (exact name match) and LLM-judge scorer (Opus) both implemented
• Variants registered: field-mapping/haiku, field-mapping/sonnet, field-mapping/opus
• Field-mapping tab in Settings → Variants renders all three variants
• Provenance recorded for field-mapping in forms/default/provenance.json under "field-mapping" key
• <VariantBadge task="field-mapping" ...> rendered on the edit/review UI where the mapping is visible
• New catalog suite catalog/experiments/field-mapping/ with _suite.md + variant pages containing metrics (recall, precision, confidence)
• catalog/experiments/_roadmap.md updated with shipped status and one-line finding

Success Metrics

• LLM-judge vs deterministic scorer deltas captured (demonstrates evaluation methodology affects measured performance)
• Ground-truth mappings committed for at least the three existing fixtures

Notes

• Mapping registry stub exists at src/services/form-documents/mapping-registry.ts; extend it
• Field-mapping generation already occurs during extraction (see src/services/form-documents/extraction.ts) — this story is about making the model swappable and evaluating

Definition of Done

• Acceptance criteria met
• Tests pass
• Type checking passes
• CI pipeline green
• Deployed and demoable