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>
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