Add redacted effective rendering

docs/internal/overview.md

@@ -30,11 +30,15 @@ module and package documentation boundary. Its implemented public primitives are
   explicitness queries, helper verification, structural mutation audit, coalesced
   intent, private before/after snapshots, and resolution metadata integration; and
 - post-resolution schema-aware report collection and validator mutation detection in
-  `validation.go`, completing the public callback lifecycle after composed input.
+  `validation.go`, completing the public callback lifecycle after composed input;
+- fixed-point tag/predicate/dependency sensitivity classification in `secret.go`; and
+- frozen-snapshot redaction and canonical effective output in `render.go`, with the
+  only upstream dumper integration isolated in `internal/yaml/write.go`.
 
 The [configuration contract](../config.md) owns implemented input, schema, decoding,
 loading lifecycle, path imports, composition, profile overlay, version checking,
-recorded resolution, semantic validation, metadata, and ownership behavior.
+recorded resolution, semantic validation, metadata, secret classification, redacted
+effective rendering, and ownership behavior.
 
 The source-extraction inventory records the application foundations assigned to
 future implementation work: