Add --no-gpu flag to disable local worker processes

- Added --no-gpu command line flag
- When --no-gpu is specified or no GPUs are detected, local worker processes are not started
- This allows running vidai as a cluster master without local GPU processing
- Useful for dedicated cluster master nodes that only manage remote clients

vidai.py

@@ -238,6 +238,12 @@ Examples:
         help='Run as cluster client (connects to master instead of starting web interface)'
     )
 
+    parser.add_argument(
+        '--no-gpu',
+        action='store_true',
+        help='Disable GPU usage and local worker processes (for cluster master mode)'
+    )
+
     args = parser.parse_args()
 
     # Update config with command line values
@@ -320,23 +326,27 @@ Examples:
                     backend_proc.wait()
                     sys.exit(1)
 
-        # Start analysis worker (only if backend is available)
+        # Determine if we should start local workers
+        should_start_workers = not args.no_gpu and len(available_backends) > 0
+
+        if args.no_gpu:
+            print("Local worker processes disabled (--no-gpu flag specified)")
+        elif not available_backends:
+            print("Local worker processes disabled (no GPUs detected)")
+
+        # Start analysis worker (only if we should start workers and backend is available)
         analysis_proc = None
-        if args.analysis_backend in available_backends:
+        if should_start_workers and args.analysis_backend in available_backends:
             analysis_cmd = [sys.executable, '-m', 'vidai.worker_analysis', args.analysis_backend]
             analysis_proc = subprocess.Popen(analysis_cmd)
             print(f"Started analysis worker for {args.analysis_backend}")
-        else:
-            print(f"Skipping analysis worker for {args.analysis_backend} (not available)")
 
-        # Start training worker (only if backend is available)
+        # Start training worker (only if we should start workers and backend is available)
         training_proc = None
-        if args.training_backend in available_backends:
+        if should_start_workers and args.training_backend in available_backends:
             training_cmd = [sys.executable, '-m', 'vidai.worker_training', args.training_backend]
             training_proc = subprocess.Popen(training_cmd)
             print(f"Started training worker for {args.training_backend}")
-        else:
-            print(f"Skipping training worker for {args.training_backend} (not available)")
 
         # Start web process
         web_cmd = [sys.executable, '-m', 'vidai.web']