chore(plugins): sync generated content mirrors

Regenerate plugins/*/skills/ from plugins/*/.apm/ after the previous
four commits, via scripts/sync-plugin-content.sh --all. The mirror is
generated output (ADR-0017) that check-plugin-content-sync's pre-push
hook diffs against .apm/; nothing here is hand-edited.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01EeH8SCbcrCAQrtymkNuhKP

plugins/bin/skills/improve-codebase-architecture/SKILL.md

@@ -6,6 +6,8 @@ description: >
   testable and AI-navigable — deepening opportunities that turn shallow modules
   into deep ones, informed by `CONTEXT.md` and `docs/adr/`. Not debugging a
   failure -> `diagnose`.
+metadata:
+  version: "1.0.0"
 ---
 
 # Improve Codebase Architecture