feat(db): wire jobs router to SQLAlchemy, add cancel endpoint

backend/app/routers/jobs.py

@@ -1,19 +1,63 @@
-from fastapi import APIRouter, HTTPException
+import json
+from datetime import datetime, timezone
 
-from app.schemas import EntityResponse, Job, ListResponse
-from app.services.store import JOBS
+from fastapi import APIRouter, Depends, HTTPException, Query
+from sqlalchemy.orm import Session
+
+from app.database import get_db
+from app.models import JobModel
+from app.schemas import EntityResponse, Job, JobStatus, ListResponse
 
 router = APIRouter(prefix='/jobs', tags=['jobs'])
 
 
+def _to_job(m: JobModel) -> Job:
+    return Job(
+        id=m.id, type=m.type, status=m.status,
+        progress=m.progress, message=m.message, error=m.error,
+        payload=json.loads(m.payload_json or '{}'),
+        result=json.loads(m.result_json or 'null'),
+        created_at=m.created_at,
+        started_at=m.started_at,
+        finished_at=m.finished_at,
+    )
+
+
 @router.get('', response_model=ListResponse[Job])
-def list_jobs() -> ListResponse[Job]:
-    return ListResponse(count=len(JOBS), items=JOBS)
+def list_jobs(
+    status: JobStatus | None = Query(default=None),
+    type: str | None = Query(default=None),
+    db: Session = Depends(get_db),
+):
+    q = db.query(JobModel)
+    if status:
+        q = q.filter(JobModel.status == status)
+    if type:
+        q = q.filter(JobModel.type == type)
+    rows = q.order_by(JobModel.created_at.desc()).all()
+    return ListResponse(count=len(rows), items=[_to_job(r) for r in rows])
 
 
 @router.get('/{job_id}', response_model=EntityResponse[Job])
-def get_job(job_id: str) -> EntityResponse[Job]:
-    for item in JOBS:
-        if item.id == job_id:
-            return EntityResponse(item=item)
+def get_job(job_id: str, db: Session = Depends(get_db)):
+    row = db.query(JobModel).filter(JobModel.id == job_id).first()
+    if not row:
         raise HTTPException(status_code=404, detail='Job not found')
+    return EntityResponse(item=_to_job(row))
+
+
+@router.post('/{job_id}/cancel', response_model=EntityResponse[Job])
+def cancel_job(job_id: str, db: Session = Depends(get_db)):
+    row = db.query(JobModel).filter(JobModel.id == job_id).first()
+    if not row:
+        raise HTTPException(status_code=404, detail='Job not found')
+    if row.status not in ('pending', 'running'):
+        raise HTTPException(
+            status_code=409,
+            detail=f'Cannot cancel job with status {row.status!r}',
+        )
+    row.status = 'cancelled'
+    row.finished_at = datetime.now(timezone.utc)
+    db.commit()
+    db.refresh(row)
+    return EntityResponse(item=_to_job(row))