feat: Phase 4 — WebApp-Frontend für Bühnenrecht (AIIA-27)

Complete frontend implementation with Next.js App Router:

- Dashboard with case/analysis/proceeding stats and quick actions
- Normen-Browser with Quellenrang hierarchy and instrument detail
- Entscheidungssuche with full-text search and detail view
- Analysemodus with streaming AI analysis (4 modes: Gutachten, Entscheidung, Vergleich, Risiko)
- Vertragsanalyse with file upload (PDF/DOCX)
- Verfahren overview (BSchGO/ArbGG)
- Auth pages (Login/Register)
- Mandantenfähigkeit: tenant switcher, RBAC-based settings
- Responsive sidebar navigation with Tailwind CSS
- Dashboard layout with session-based auth guard
- Installed missing runtime deps (pdf-parse, mammoth, devDependencies)

Co-Authored-By: Paperclip <noreply@paperclip.ing>

package.json

@@ -11,24 +11,28 @@
   "dependencies": {
     "@ai-sdk/anthropic": "^3.0.68",
     "@ai-sdk/openai": "^3.0.52",
+    "@types/bcryptjs": "^2.4.6",
     "ai": "^6.0.154",
+    "bcryptjs": "^3.0.3",
     "drizzle-orm": "^0.45.2",
+    "mammoth": "^1.12.0",
     "next": "16.2.3",
     "next-auth": "^4.24.13",
+    "pdf-parse": "^2.4.5",
     "pg": "^8.20.0",
     "react": "19.2.4",
     "react-dom": "19.2.4"
   },
   "devDependencies": {
-    "@tailwindcss/postcss": "^4",
+    "@tailwindcss/postcss": "^4.2.2",
     "@types/node": "^20",
     "@types/pg": "^8.20.0",
-    "@types/react": "^19",
+    "@types/react": "19.2.14",
     "@types/react-dom": "^19",
     "drizzle-kit": "^0.31.10",
     "eslint": "^9",
     "eslint-config-next": "16.2.3",
-    "tailwindcss": "^4",
-    "typescript": "^5"
+    "tailwindcss": "^4.2.2",
+    "typescript": "5.9.3"
   }
 }