Move prompts into embedded Markdown assets

docs/public-contract.md

@@ -11,6 +11,7 @@ This contract covers:
 - transcript output schema selection
 - process report schema metadata
 - stable validator key identifiers in report/diagnostics records
+- prompt metadata identifiers in diagnostics
 - diagnostics directory behavior
 - stdout/stderr and exit-code behavior
 - secret redaction guarantees
@@ -103,6 +104,15 @@ When diagnostics directory creation succeeds, Audita writes run artifacts includ
 
 Retention behavior is controlled by configured retention mode; failed runs are retained.
 
+Diagnostics metadata for LLM interactions may include semi-public prompt identifiers:
+- `prompt_id`
+- `prompt_version`
+- `prompt_source`
+- `embedded_path`
+- `sha256`
+
+These are diagnostic identifiers, not user-facing prompt override controls.
+
 ## Stdout/stderr behavior
 
 Success behavior: