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

package.json

@@ -3,6 +3,18 @@
   "version": "4.0.0",
   "description": "560+ agentic skills for Claude Code, Gemini CLI, Cursor, Antigravity & more. Installer CLI.",
   "license": "MIT",
+  "scripts": {
+    "validate": "python3 scripts/validate_skills.py",
+    "validate:strict": "python3 scripts/validate_skills.py --strict",
+    "index": "python3 scripts/generate_index.py",
+    "readme": "python3 scripts/update_readme.py",
+    "chain": "npm run validate && npm run index && npm run readme",
+    "catalog": "node scripts/build-catalog.js",
+    "build": "npm run chain && npm run catalog"
+  },
+  "dependencies": {
+    "yaml": "^2.8.2"
+  },
   "repository": {
     "type": "git",
     "url": "https://github.com/sickn33/antigravity-awesome-skills.git"