feat: implement automation module

- Event-based triggers (Phase 1):
  - Trigger/TriggerLog models with field_change type
  - TriggerService for condition evaluation and action execution
  - Trigger CRUD API endpoints
  - Task integration (status, assignee, priority changes)
  - Frontend: TriggerList, TriggerForm components

- Weekly reports (Phase 2):
  - ScheduledReport/ReportHistory models
  - ReportService for stats generation
  - APScheduler for Friday 16:00 job
  - Report preview/generate/history API
  - Frontend: WeeklyReportPreview, ReportHistory components

- Tests: 23 new tests (14 triggers + 9 reports)
- OpenSpec: add-automation change archived

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

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

backend/app/api/reports/router.py

@@ -0,0 +1,146 @@
+from fastapi import APIRouter, Depends, HTTPException, status
+from sqlalchemy.orm import Session
+from typing import Optional
+
+from app.core.database import get_db
+from app.models import User, ReportHistory, ScheduledReport
+from app.schemas.report import (
+    WeeklyReportContent, ReportHistoryListResponse, ReportHistoryItem,
+    GenerateReportResponse, ReportSummary
+)
+from app.middleware.auth import get_current_user
+from app.services.report_service import ReportService
+
+router = APIRouter(tags=["reports"])
+
+
+@router.get("/api/reports/weekly/preview", response_model=WeeklyReportContent)
+async def preview_weekly_report(
+    db: Session = Depends(get_db),
+    current_user: User = Depends(get_current_user),
+):
+    """
+    Preview the weekly report for the current user.
+    Shows what would be included in the next weekly report.
+    """
+    content = ReportService.get_weekly_stats(db, current_user.id)
+
+    return WeeklyReportContent(
+        week_start=content["week_start"],
+        week_end=content["week_end"],
+        generated_at=content["generated_at"],
+        projects=content["projects"],
+        summary=ReportSummary(**content["summary"]),
+    )
+
+
+@router.post("/api/reports/weekly/generate", response_model=GenerateReportResponse)
+async def generate_weekly_report(
+    db: Session = Depends(get_db),
+    current_user: User = Depends(get_current_user),
+):
+    """
+    Manually trigger weekly report generation for the current user.
+    """
+    # Generate report
+    report_history = ReportService.generate_weekly_report(db, current_user.id)
+
+    if not report_history:
+        raise HTTPException(
+            status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,
+            detail="Failed to generate report",
+        )
+
+    # Send notification
+    ReportService.send_report_notification(db, current_user.id, report_history.content)
+    db.commit()
+
+    summary = report_history.content.get("summary", {})
+
+    return GenerateReportResponse(
+        message="Weekly report generated successfully",
+        report_id=report_history.id,
+        summary=ReportSummary(
+            completed_count=summary.get("completed_count", 0),
+            in_progress_count=summary.get("in_progress_count", 0),
+            overdue_count=summary.get("overdue_count", 0),
+            total_tasks=summary.get("total_tasks", 0),
+        ),
+    )
+
+
+@router.get("/api/reports/history", response_model=ReportHistoryListResponse)
+async def list_report_history(
+    limit: int = 10,
+    offset: int = 0,
+    db: Session = Depends(get_db),
+    current_user: User = Depends(get_current_user),
+):
+    """
+    List report history for the current user.
+    """
+    # Get scheduled report for this user
+    scheduled_report = db.query(ScheduledReport).filter(
+        ScheduledReport.recipient_id == current_user.id,
+    ).first()
+
+    if not scheduled_report:
+        return ReportHistoryListResponse(reports=[], total=0)
+
+    # Get history
+    total = db.query(ReportHistory).filter(
+        ReportHistory.report_id == scheduled_report.id,
+    ).count()
+
+    history = db.query(ReportHistory).filter(
+        ReportHistory.report_id == scheduled_report.id,
+    ).order_by(ReportHistory.generated_at.desc()).offset(offset).limit(limit).all()
+
+    return ReportHistoryListResponse(
+        reports=[
+            ReportHistoryItem(
+                id=h.id,
+                report_id=h.report_id,
+                generated_at=h.generated_at,
+                content=h.content,
+                status=h.status,
+                error_message=h.error_message,
+            ) for h in history
+        ],
+        total=total,
+    )
+
+
+@router.get("/api/reports/history/{report_id}")
+async def get_report_detail(
+    report_id: str,
+    db: Session = Depends(get_db),
+    current_user: User = Depends(get_current_user),
+):
+    """
+    Get detailed content of a specific report.
+    """
+    report = db.query(ReportHistory).filter(ReportHistory.id == report_id).first()
+
+    if not report:
+        raise HTTPException(
+            status_code=status.HTTP_404_NOT_FOUND,
+            detail="Report not found",
+        )
+
+    # Check ownership
+    scheduled_report = report.report
+    if scheduled_report.recipient_id != current_user.id and not current_user.is_system_admin:
+        raise HTTPException(
+            status_code=status.HTTP_403_FORBIDDEN,
+            detail="Access denied",
+        )
+
+    return ReportHistoryItem(
+        id=report.id,
+        report_id=report.report_id,
+        generated_at=report.generated_at,
+        content=report.content,
+        status=report.status,
+        error_message=report.error_message,
+    )