feat: add background tasks monitoring dashboard

Adds a unified view of all background tasks (imports and test runs)
under Platform Monitoring. Includes real-time status polling,
statistics overview, and task history.

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

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

app/services/background_tasks_service.py

@@ -0,0 +1,116 @@
+# app/services/background_tasks_service.py
+"""
+Background Tasks Service
+Service for monitoring background tasks across the system
+"""
+
+from datetime import UTC, datetime
+
+from sqlalchemy import desc, func
+from sqlalchemy.orm import Session
+
+from models.database.marketplace_import_job import MarketplaceImportJob
+from models.database.test_run import TestRun
+
+
+class BackgroundTasksService:
+    """Service for monitoring background tasks"""
+
+    def get_import_jobs(
+        self, db: Session, status: str | None = None, limit: int = 50
+    ) -> list[MarketplaceImportJob]:
+        """Get import jobs with optional status filter"""
+        query = db.query(MarketplaceImportJob)
+        if status:
+            query = query.filter(MarketplaceImportJob.status == status)
+        return query.order_by(desc(MarketplaceImportJob.created_at)).limit(limit).all()
+
+    def get_test_runs(
+        self, db: Session, status: str | None = None, limit: int = 50
+    ) -> list[TestRun]:
+        """Get test runs with optional status filter"""
+        query = db.query(TestRun)
+        if status:
+            query = query.filter(TestRun.status == status)
+        return query.order_by(desc(TestRun.timestamp)).limit(limit).all()
+
+    def get_running_imports(self, db: Session) -> list[MarketplaceImportJob]:
+        """Get currently running import jobs"""
+        return (
+            db.query(MarketplaceImportJob)
+            .filter(MarketplaceImportJob.status == "processing")
+            .all()
+        )
+
+    def get_running_test_runs(self, db: Session) -> list[TestRun]:
+        """Get currently running test runs"""
+        return db.query(TestRun).filter(TestRun.status == "running").all()
+
+    def get_import_stats(self, db: Session) -> dict:
+        """Get import job statistics"""
+        today_start = datetime.now(UTC).replace(hour=0, minute=0, second=0, microsecond=0)
+
+        stats = db.query(
+            func.count(MarketplaceImportJob.id).label("total"),
+            func.sum(
+                func.case((MarketplaceImportJob.status == "processing", 1), else_=0)
+            ).label("running"),
+            func.sum(
+                func.case(
+                    (MarketplaceImportJob.status.in_(["completed", "completed_with_errors"]), 1),
+                    else_=0,
+                )
+            ).label("completed"),
+            func.sum(
+                func.case((MarketplaceImportJob.status == "failed", 1), else_=0)
+            ).label("failed"),
+        ).first()
+
+        today_count = (
+            db.query(func.count(MarketplaceImportJob.id))
+            .filter(MarketplaceImportJob.created_at >= today_start)
+            .scalar()
+            or 0
+        )
+
+        return {
+            "total": stats.total or 0,
+            "running": stats.running or 0,
+            "completed": stats.completed or 0,
+            "failed": stats.failed or 0,
+            "today": today_count,
+        }
+
+    def get_test_run_stats(self, db: Session) -> dict:
+        """Get test run statistics"""
+        today_start = datetime.now(UTC).replace(hour=0, minute=0, second=0, microsecond=0)
+
+        stats = db.query(
+            func.count(TestRun.id).label("total"),
+            func.sum(func.case((TestRun.status == "running", 1), else_=0)).label("running"),
+            func.sum(func.case((TestRun.status == "passed", 1), else_=0)).label("completed"),
+            func.sum(
+                func.case((TestRun.status.in_(["failed", "error"]), 1), else_=0)
+            ).label("failed"),
+            func.avg(TestRun.duration_seconds).label("avg_duration"),
+        ).first()
+
+        today_count = (
+            db.query(func.count(TestRun.id))
+            .filter(TestRun.timestamp >= today_start)
+            .scalar()
+            or 0
+        )
+
+        return {
+            "total": stats.total or 0,
+            "running": stats.running or 0,
+            "completed": stats.completed or 0,
+            "failed": stats.failed or 0,
+            "today": today_count,
+            "avg_duration": round(stats.avg_duration or 0, 1),
+        }
+
+
+# Singleton instance
+background_tasks_service = BackgroundTasksService()