gpt-5.3-codex review Phase 3

.github/instructions/services.instructions.md

@@ -73,6 +73,7 @@ module, not in a cross-service import.
   [sources](../../src/transcription/services/sources.py).
 - Category mapping, retry behavior, and translation boundaries are defined in
   [error-handling instructions](./error-handling.instructions.md).
+- Service-edge exception translation must be deterministic: map to canonical categories and preserve clear provider->service->API/UI boundaries.
 
 ## Checklist
 
@@ -122,14 +123,15 @@ Atomicity rules:
 ## V4 Contract Alignment
 
 - Treat `docs/ver4/` as the active architecture and requirements baseline.
-- Treat `docs/ver4/history.md` and `docs-v4x-archive` as historical-only references.
+- Legacy V4 revision trees are out of scope for active implementation decisions and must not be referenced as authoritative service guidance.
+- Treat `src/transcription/db/models.py` as runtime schema ground truth and `docs/ver4/schema_v4.md` as the field-accurate contract mirror.
 - `Job.status` success path is `TRANSCRIBED`.
 - `JobSource.status` is queue/projection state only (`PENDING`, `TRANSCRIBED`, `FAILED`, `CANCELLED`).
 - Source ingest may normalize media before persistence; persisted bytes/hash are canonical for processing and provenance.
 - `ExecutionAttempt` is append-only evidence history; do not mutate historical attempt rows in runtime code.
 - `Source.raw_transcription` is a projection, not authoritative history.
 - Service/UI read paths that touch relationships must be eager-loaded for `lazy="raise"` compatibility.
-- If evidence-related model fields change, update `docs/ver4/schema_v4.md` in the same change.
+- If model fields, enums, constraints, indexes, or relationship-loading semantics change, update `docs/ver4/schema_v4.md` in the same change.
 
 # Service Composition