Harden YOLO compatibility preflight

scripts/README.md

@@ -23,6 +23,16 @@ datasets, vector FeatureCollection content, vector feature summary, persisted
 QA/QC metrics, creates metadata/report/vector GeoJSON exports, lists exports
 and downloads the JSON/GeoJSON/HTML artifacts through the frontend proxy.
 
+Verify a configured local YOLO model without running inference:
+
+```bash
+python scripts/yolo_preflight.py --model-path /absolute/path/to/model.pt --tile-manifest-path /absolute/path/to/manifest.json --check-model-load --json
+```
+
+The model-load smoke is opt-in, requires real optional AI dependencies, refuses
+`--assume-dependencies`, loads only the supplied local file and does not download
+weights or run prediction.
+
 Clean old offline demo export artifacts without touching uploaded source data:
 
 ```bash

scripts/run_readiness_check.sh

@@ -37,6 +37,7 @@ ${PYTHON_BIN} scripts/validate_m13_codex_assets.py
 ${PYTHON_BIN} scripts/validate_m14_launch_assets.py
 ${PYTHON_BIN} -m py_compile scripts/gis_import_smoke.py
 ${PYTHON_BIN} -m py_compile scripts/seed_demo_workflow.py
+${PYTHON_BIN} -m py_compile scripts/yolo_preflight.py
 ${PYTHON_BIN} -m py_compile scripts/cleanup_demo_artifacts.py
 ${PYTHON_BIN} -m py_compile backend/scripts/cleanup_demo_artifacts.py
 ${PYTHON_BIN} -m compileall backend/app

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: