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/modules/report_generation/models.py

@@ -0,0 +1,100 @@
+"""SQLAlchemy models for report generation
+
+Tables:
+- generated_reports: Stores report metadata and generation status
+"""
+from sqlalchemy import Column, String, Text, DateTime, Integer, ForeignKey, Index, JSON
+from sqlalchemy.orm import relationship
+from datetime import datetime
+import uuid
+import enum
+from app.core.database import Base
+
+
+class ReportStatus(str, enum.Enum):
+    """Report generation status"""
+    PENDING = "pending"
+    COLLECTING_DATA = "collecting_data"
+    GENERATING_CONTENT = "generating_content"
+    ASSEMBLING_DOCUMENT = "assembling_document"
+    COMPLETED = "completed"
+    FAILED = "failed"
+
+
+class GeneratedReport(Base):
+    """Generated report model for incident reports"""
+
+    __tablename__ = "generated_reports"
+
+    report_id = Column(
+        String(36), primary_key=True, default=lambda: str(uuid.uuid4()),
+        comment="Unique report identifier (UUID)"
+    )
+    room_id = Column(
+        String(36), ForeignKey("incident_rooms.room_id", ondelete="CASCADE"),
+        nullable=False, comment="Reference to incident room"
+    )
+
+    # Generation metadata
+    generated_by = Column(
+        String(255), nullable=False,
+        comment="User email who triggered report generation"
+    )
+    generated_at = Column(
+        DateTime, default=datetime.utcnow, nullable=False,
+        comment="Report generation timestamp"
+    )
+
+    # Status tracking
+    status = Column(
+        String(30), default=ReportStatus.PENDING.value, nullable=False,
+        comment="Current generation status"
+    )
+    error_message = Column(
+        Text, nullable=True,
+        comment="User-friendly error message if generation failed"
+    )
+
+    # DIFY AI metadata
+    dify_message_id = Column(
+        String(100), nullable=True,
+        comment="DIFY API message ID for tracking"
+    )
+    dify_conversation_id = Column(
+        String(100), nullable=True,
+        comment="DIFY conversation ID"
+    )
+    prompt_tokens = Column(
+        Integer, nullable=True,
+        comment="Number of prompt tokens used"
+    )
+    completion_tokens = Column(
+        Integer, nullable=True,
+        comment="Number of completion tokens used"
+    )
+
+    # Report content
+    report_title = Column(
+        String(255), nullable=True,
+        comment="Generated report title"
+    )
+    report_json = Column(
+        JSON, nullable=True,
+        comment="Parsed AI output as JSON"
+    )
+    docx_storage_path = Column(
+        String(500), nullable=True,
+        comment="Path to generated .docx file in MinIO or local storage"
+    )
+
+    # Relationship
+    room = relationship("IncidentRoom", backref="reports")
+
+    # Indexes
+    __table_args__ = (
+        Index("ix_generated_reports_room_date", "room_id", "generated_at"),
+        Index("ix_generated_reports_status", "status"),
+    )
+
+    def __repr__(self):
+        return f"<GeneratedReport {self.report_id} status={self.status}>"