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/api/v1/admin/__init__.py

@@ -27,6 +27,7 @@ from fastapi import APIRouter
 from . import (
     audit,
     auth,
+    background_tasks,
     code_quality,
     companies,
     content_pages,
@@ -118,8 +119,10 @@ router.include_router(marketplace.router, tags=["admin-marketplace"])
 # Platform Administration
 # ============================================================================
 
-# Include monitoring endpoints (placeholder for future implementation)
-# router.include_router(monitoring.router, tags=["admin-monitoring"])
+# Include background tasks monitoring endpoints
+router.include_router(
+    background_tasks.router, prefix="/background-tasks", tags=["admin-background-tasks"]
+)
 
 # Include audit logging endpoints
 router.include_router(audit.router, tags=["admin-audit"])