T08a: Frontend DMS + Tags + Permissions UI — 33 tests, tsc clean, vite build pass

- DMS file browser: folder tree + file grid + upload dropzone + search + preview modal
- DMS share dialog: user/group share + public share links with password+expiry
- DMS bulk actions: bulk move + bulk delete with confirm dialogs
- DMS trash view: deleted files list with restore button
- Tags: TagPicker on company/contact detail pages (new tabs tab)
- Tags: TagCloud + BulkTagDialog for bulk tag assignment
- Permissions: share link creation, permission display, copy-link button
- API clients: dms.ts, tags.ts, permissions.ts
- Routes: /dms, /dms/trash added to router
- Sidebar: DMS nav link updated
- i18n: de.json + en.json translations for DMS/Tags/Permissions
- 33 new tests (5 test files), full regression 276/276 pass
- tsc --noEmit: 0 errors, vite build: 252 modules

.a0/next_steps.md

@@ -1,8 +1,7 @@
 # LeoCRM — Next Steps
 1. **User decision needed**: Which task next?
-   - T06: Mail Plugin Backend (IMAP/SMTP, Threading, Templates, Rules, PGP)
-   - T08a: DMS Frontend (prerequisite T04 ✅ — now unblocked)
-   - T08b: Calendar Frontend (prerequisite T05 ✅ — now unblocked)
+   - T08a: DMS Frontend (prerequisite T04 ✅, T07b ✅ — unblocked)
+   - T08c: Mail Frontend (prerequisite T06 ✅ — now unblocked)
    - T10: Monitoring, Performance, Documentation & Environment Config
 2. After task selection: delegate to implementation_engineer with briefing
 3. After implementation: test_debug_engineer for validation