Protect transcript refinement resume semantics

docs/internal/stage-polish.md

@@ -28,10 +28,26 @@ Run Audita polishing on base transcript and produce polished transcript.
 - polished transcript schema validation is mandatory.
 - report output is config-gated.
 
+## Resume Semantics
+
+The versioned semantic fingerprint covers the Audita service endpoint, model,
+validation model, module set, transcript description, output schema, selected
+external configuration path, and canonical polished-transcript identity. Module
+ordering is normalized because the configured modules form a set. Audita's
+executable, timeouts, concurrency, report and debug behavior, work retention,
+and credential environment name are operational and do not invalidate a
+successful result.
+
+Narratio can fingerprint a selected model, module, or configuration identifier,
+but it cannot inspect content that Audita privately resolves behind that stable
+identifier. Force `polish` after changing such private content without changing
+its identifier.
+
 ## Related Contracts And Tests
 
 - [Audita](../integrations/audita.md) owns subprocess, validation, and failure
   semantics.
 - [Configuration](../config.md#pipeline) owns operator-selected Audita values.
 - Implementation and tests: `internal/stage/polish.go`,
-  `internal/stage/polish_test.go`
+  `internal/stage/polish_test.go`,
+  `internal/stage/semantic_contracts_refinement.go`