Redesign jobs dashboard with unified table and progress bar

- Add overall progress bar showing completed/active/failed counts
- Unify all job types into single table with Type column
- Simplify status to Working/Pending/Failed badges
- Remove NPM "Coming Soon" section
- Add get_recent_activity() function for future activity feed
- Fix dark mode CSS using CSS variables

backend/app/pypi_cache_worker.py

@@ -600,6 +600,40 @@ def get_active_tasks(db: Session, limit: int = 50) -> List[dict]:
     ]
 
 
+def get_recent_activity(db: Session, limit: int = 20) -> List[dict]:
+    """
+    Get recent task completions and failures for activity feed.
+
+    Args:
+        db: Database session.
+        limit: Maximum number of items to return.
+
+    Returns:
+        List of recent activity items sorted by time descending.
+    """
+    # Get recently completed and failed tasks
+    tasks = (
+        db.query(PyPICacheTask)
+        .filter(PyPICacheTask.status.in_(["completed", "failed"]))
+        .filter(PyPICacheTask.completed_at != None)
+        .order_by(PyPICacheTask.completed_at.desc())
+        .limit(limit)
+        .all()
+    )
+
+    return [
+        {
+            "id": str(task.id),
+            "package": task.package_name,
+            "status": task.status,
+            "type": "pypi",
+            "error": task.error_message if task.status == "failed" else None,
+            "completed_at": task.completed_at.isoformat() if task.completed_at else None,
+        }
+        for task in tasks
+    ]
+
+
 def retry_failed_task(db: Session, package_name: str) -> Optional[PyPICacheTask]:
     """
     Reset a failed task to retry.