Update instructions, agents, skills - part 1

.github/instructions/documentation-sync.instructions.md

@@ -7,6 +7,11 @@ applyTo: 'src/transcription/**/*.py'
 
 Keep docs in sync in the same change whenever implementation alters a documented contract, behavior, or roadmap decision.
 
+Documentation targets below always refer to the **current** baseline. `docs/index.md` states which
+baseline that is; resolve any version-specific document from there. Never cite a superseded version
+tree by name in this file or in the docs you update — retired revision trees are not authority, and
+`tests/test_meta_contract_guards.py` fails active contract files that route authority through them.
+
 ## Update documentation when any of these change
 
 1. **Schema/Data contract**
@@ -27,7 +32,8 @@ Keep docs in sync in the same change whenever implementation alters a documented
 
 5. **Roadmap/scope decisions**
    - Version targets, sequencing, deferrals, and accepted alternatives.
-   - **Required doc update:** `docs/roadmap_plan.md` and related backlog docs (for example `docs/ver4.8/feature_backlog_v4_8.md`).
+   - **Required doc update:** `docs/roadmap_plan.md`, plus any backlog or feature document for the
+     current baseline. Locate it through `docs/index.md` rather than assuming a version-named path.
 
 ## Working rule