test(field-mapper): wire @tested markers to parity contract

- mapper-parity.test.ts의 @covers 4개에 대응하는 @tested 역링크 추가
- airtable/seatable/supabase field-mapper + provider-registry → @tested mapper-parity.test.ts
- 양방향 테스트 커버리지 링크 무결성 완성

src/services/airtable-field-mapper.ts

@@ -8,6 +8,7 @@
  * @handbook 4.4-provider-abstraction
  * @handbook 7.3-read-only-field-protection
  * @tested tests/services/airtable-field-mapper.test.ts
+ * @tested tests/services/mapper-parity.test.ts
  */
 
 import type { FieldTypeMapper, StandardFieldType } from '../types';

src/services/provider-registry.ts

@@ -11,6 +11,7 @@
  *
  * @handbook 4.4-provider-abstraction
  * @tested tests/services/provider-registry.test.ts
+ * @tested tests/services/mapper-parity.test.ts
  * @tested e2e:tests/e2e/run-seatable-e2e.mjs
  */
 

src/services/seatable-field-mapper.ts

@@ -8,6 +8,7 @@
  * @handbook 4.4-provider-abstraction
  * @handbook 7.3-read-only-field-protection
  * @tested tests/services/seatable-field-mapper.test.ts
+ * @tested tests/services/mapper-parity.test.ts
  * @tested e2e:tests/e2e/run-seatable-e2e.mjs
  */
 

src/services/supabase-field-mapper.ts

@@ -9,6 +9,7 @@
  * @handbook 4.4-provider-abstraction
  * @handbook 7.3-read-only-field-protection
  * @tested tests/services/supabase-field-mapper.test.ts
+ * @tested tests/services/mapper-parity.test.ts
  */
 
 import type { FieldTypeMapper, StandardFieldType } from '../types';