feat: Add AI report generation with DIFY integration

- Add Users table for display name resolution from AD authentication
- Integrate DIFY AI service for report content generation
- Create docx assembly service with image embedding from MinIO
- Add REST API endpoints for report generation and download
- Add WebSocket notifications for generation progress
- Add frontend UI with progress modal and download functionality
- Add integration tests for report generation flow

Report sections (Traditional Chinese):
- 事件摘要 (Summary)
- 時間軸 (Timeline)
- 參與人員 (Participants)
- 處理過程 (Resolution Process)
- 目前狀態 (Current Status)
- 最終處置結果 (Final Resolution)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

app/main.py

@@ -16,6 +16,7 @@ from app.modules.chat_room import router as chat_room_router
 from app.modules.chat_room.services.template_service import template_service
 from app.modules.realtime import router as realtime_router
 from app.modules.file_storage import router as file_storage_router
+from app.modules.report_generation import router as report_generation_router
 
 # Frontend build directory
 FRONTEND_DIR = Path(__file__).parent.parent / "frontend" / "dist"
@@ -51,6 +52,7 @@ app.include_router(auth_router)
 app.include_router(chat_room_router)
 app.include_router(realtime_router)
 app.include_router(file_storage_router)
+app.include_router(report_generation_router)
 
 
 @app.on_event("startup")