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/index.en.md

@@ -22,6 +22,7 @@ tools**. Users maintain a shared catalog of tools, submit ratings
 | **Record costs** | Enter license and cost models per tool | Premium |
 | **Analytics** | Statistics, top tools, distributions | Everyone |
 | **Trash** | Restore soft-deleted tools or delete them permanently | Premium |
+| **Import** | Create multiple tools via CSV, JSON or YAML | Admin (premium) |
 | **Admin** | User management, audit log, system information | Admin |
 | **Redundancy detection** | Automatic duplicate detection | Admin |