docs: cut to v0.9.0 with unified .de/.en naming

- Remove all prior release notes and version snapshots (v0.6.0-v0.8.6)
- Rename handbook to *.de.md; keep *.en.md
- New release notes v0.9.0.de.md/.en.md with v0.9.0 snapshot
- generate-docs.mjs: .de/.en convention incl. search index and en-fallback
- docs.tsx: release fallback now uses version.de.md
- Wording: neutral tagline, anonymous user, no gender forms
- Add docs/examples/import-tools.yaml and link from administration docs

artifacts/toolrate/src/i18n/locales/en.json

@@ -69,7 +69,7 @@
   },
   "home": {
     "welcome": "Welcome to toolr",
-    "tagline": "The community hub where engineers honestly rate the tools they use daily.",
+    "tagline": "Rate your Tool.",
     "totalTools": "Total Tools",
     "totalRatings": "Total Ratings",
     "avgRating": "Avg Rating",
@@ -189,7 +189,7 @@
     "nameOptional": "Name (Optional)",
     "nameLabel": "Name",
     "anonymousPlaceholder": "Anonymous",
-    "anonymousEngineer": "Anonymous Engineer",
+    "anonymousEngineer": "Anonymous User",
     "beFirstToReview": "Be the first to share your thoughts on this tool.",
     "shareExperience": "Share your experience with {{name}}",
     "score": "Score",