Add generic raw output validators

docs/internal/pipeline.md

@@ -188,6 +188,9 @@ lane, module, source, chunk, schema, session, reference, LLM client/profile,
 binding option, and run metadata context. Merge validators also receive the
 ordered extract outputs used by the merge, and normalize validators receive the
 accepted merge output. Empty raw validation chains approve output by default.
+Response-schema provenance may include in-memory JSON schema bytes for
+validators. Those bytes are omitted from manifests, diagnostics, and encoded
+output files.
 
 Resolved validator chains come from central default mappings unless a
 stage-local config override is set on `chunk`, lane `extract`, lane `merge`, or