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

docs/releases/v0.9.0/handbook/tastatur.en.md

@@ -0,0 +1,36 @@
+
+# Keyboard shortcuts & command palette
+
+## Command palette
+
+The command palette is the central quick navigation:
+
+- Open with **`⌘K`** (macOS) or **`Ctrl+K`** (Windows/Linux).
+- Alternatively via the search bar at the top right ("Search tools… ⌘K") or the
+  search icon on mobile devices.
+
+### Empty state
+
+Without input, the palette shows:
+
+- **Recently viewed** — the last 5 tools you visited.
+- **Navigation** — browse tools, add tool, analytics as well as
+  (depending on permissions) watchlist, trash and admin.
+
+### Search
+
+Type to search for tools live (max. 10 results, incl. rating
+`X.X★`).
+
+## Overview of keyboard shortcuts
+
+| Shortcut | Action |
+| --- | --- |
+| `⌘K` / `Ctrl+K` | Open command palette |
+| `/` | Focus search in the "Browse tools" area |
+
+## Additional notes
+
+- **Recently viewed** is stored locally in the browser (max. 5 entries).
+- The sidebar (left navigation) can be collapsed on desktop; the
+  breadcrumb at the top shows your current location.