Create new cluster master instance per start

- Prevents active_jobs from persisting across server restarts
- Eliminates leftover job tracking from previous runs
- Ensures clean state for each server start

vidai/cluster_master.py

@@ -1457,12 +1457,14 @@ def start_cluster_master(host: str = '0.0.0.0', port: int = 5003, shared_dir: st
         else:
             weight_explicit = True
 
-    cluster_master.host = host
-    cluster_master.port = port
-    cluster_master.shared_dir = shared_dir
-    cluster_master.weight = weight
-    cluster_master.weight_explicit = weight_explicit
-    asyncio.run(cluster_master.start())
+    # Create a new cluster master instance for each start
+    master = ClusterMaster()
+    master.host = host
+    master.port = port
+    master.shared_dir = shared_dir
+    master.weight = weight
+    master.weight_explicit = weight_explicit
+    asyncio.run(master.start())
 
 
 if __name__ == "__main__":