feat(import): bulk tool import (CSV/JSON/YAML) for admins; NetBox-style help button

- Add POST /admin/tools/import with format auto-detect, CSV delimiters
  (comma/semicolon/tab), per-row validation via CreateToolBody, bulk insert,
  audit log entries per imported tool; gated by new 'tool-import' feature
  flag (premium/enterprise; admins always pass)
- Add tool-import-dialog UI (format tabs, delimiter select, textarea, file
  upload, result/error list) behind hasFeature('tool-import')
- Replace FieldHelp question marks and bare GuideHelp links with a NetBox-style
  'Hilfe/Help' outline button (HelpCircle + text) in form headers only
- Sync locales to 482 keys per language (de/en), update handbook docs
  (administration import section, index/plaene feature tables), regenerate
  API client + zod schemas, add yaml dependency

docs/handbook/plaene.en.md

@@ -26,6 +26,7 @@ Premium/Enterprise unlock the following features:
 | `watchlist` | Favorites list | [Watchlist](/docs/handbook/watchlist) |
 | `trash` | Trash (soft-deleted tools) | [Trash](/docs/handbook/papierkorb) |
 | `costs` | Record cost/license models | [Recording costs](/docs/handbook/kosten) |
+| `tool-import` | Import tools via CSV/JSON/YAML (admin) | [Administration](/docs/handbook/administration) |
 
 If you are missing a feature, the app shows an **upgrade notice** with a link
 to the plan management.