Complete Phase 17 parity fixture suite

docs/rewrite-notes.md

@@ -98,7 +98,6 @@ Implemented:
 - Generic JSON diagnostics primitives for LLM interactions (request metadata, request payload, response payload, optional error payload) with secret redaction.
 
 Not yet implemented in runtime pipeline:
-- Python parity fixture suite and parity verification workflow.
 - Operational hardening beyond current Phase 16 runtime/reporting/diagnostics scope.
 - Rollout/Python retirement work.
 
@@ -238,7 +237,7 @@ Not implemented in Phase 8 (by design):
 
 ## Remaining work plan
 
-Next recommended phase: **Phase 17 (Python parity fixture suite)**.
+Next recommended phase: **Phase 18 (operational hardening and subprocess integration)**.
 
 ## Phase 9: Structured LLM client and scheduler infrastructure
 
@@ -527,6 +526,8 @@ Intentionally deferred:
 
 ## Phase 17: Python parity fixture suite
 
+Completed.
+
 ### Purpose
 
 Establish confidence that the Go implementation matches the behavior and safety posture of the initial Python implementation.
@@ -566,6 +567,35 @@ The repository has a durable test suite demonstrating that the Go implementation
 - Unintentional compatibility breaks are fixed.
 - `go test ./...` passes.
 
+### Phase 17 completion status
+
+Implemented:
+- Durable parity fixture harness in Go test path (`internal/cli/parity_test.go`).
+- Representative parity fixture corpus under `internal/cli/testdata/parity`.
+- Fake LLM proposal/validator fixtures driving deterministic parity tests.
+- Default full-pipeline parity coverage including sequence/order and repeated glossary naming:
+  - `glossary_1`
+  - `homophones`
+  - `glossary_2`
+  - `spoken_word`
+  - `grammar`
+- Parity checks that are strict for deterministic contract fields:
+  - transcript content
+  - module order and instance names
+  - applied/skipped/rejected counts
+  - report status and failed-module metadata
+- Parity checks that ignore nondeterministic metadata fields:
+  - timestamps
+  - run IDs
+  - temp/absolute paths
+  - provider token usage details
+- Documentation of intentional Python-vs-Go differences and honest open parity gaps in `docs/python-parity.md`.
+- Normal `go test ./...` path remains independent of real LLM credentials and Python dependencies.
+
+Intentionally deferred:
+- Phase 18 operational hardening and subprocess integration expansion.
+- Phase 19 rollout and Python retirement work.
+
 ## Phase 18: Operational hardening and subprocess integration
 
 ### Purpose