Harden YOLO compatibility preflight

scripts/yolo_preflight.py

@@ -26,8 +26,15 @@ def main() -> int:
         action="store_true",
         help="Skip checking installed ultralytics/torch packages; useful for validating local paths on non-AI machines.",
     )
+    parser.add_argument(
+        "--check-model-load",
+        action="store_true",
+        help="Explicitly load the configured local model file to verify Ultralytics compatibility; no inference is run.",
+    )
     parser.add_argument("--json", action="store_true", help="Print JSON output only.")
     args = parser.parse_args()
+    if args.check_model_load and args.assume_dependencies:
+        parser.error("--check-model-load cannot be combined with --assume-dependencies")
 
     settings = Settings(
         yolo_enabled=args.enabled or bool(args.model_path),
@@ -38,6 +45,7 @@ def main() -> int:
         settings=settings,
         tile_manifest_path=args.tile_manifest_path,
         assume_dependencies=args.assume_dependencies,
+        check_model_load=args.check_model_load,
     )
 
     if args.json: