chore: implement repo improvements plan (npm scripts, docs, catalog CI, i18n, validator)

- Add npm scripts: validate, validate:strict, index, readme, chain, catalog, build
- Align docs to V4 and 560 skills (GETTING_STARTED, FAQ, BUNDLES, MAINTENANCE, vietnamese)
- build-catalog: output to data/ for catalog, bundles, aliases; add to CI and drift check
- Add yaml dep, Node setup and catalog step in CI; extend auto-commit and drift msg
- Translate CI and MAINTENANCE to English; update CI_DRIFT_FIX and maintenance routine
- QUALITY_BAR/CONTRIBUTING: canonical validator npm run validate; legacy note in validate-skills.js

docs/QUALITY_BAR.md

@@ -57,8 +57,9 @@ We also categorize skills by who maintains them:
 
 ## How to Validate Your Skill
 
-Run the validator script before submitting a PR:
+The canonical validator is `scripts/validate_skills.py`. Run `npm run validate` (or `npm run validate:strict`) before submitting a PR:
 
 ```bash
-python3 scripts/validate_skills.py --strict
+npm run validate       # soft mode (warnings only)
+npm run validate:strict  # strict mode (CI uses this)
 ```