Add geosure data

pipeline/download/geosure.py

@@ -0,0 +1,44 @@
+"""Download OS GeoSure ground stability data (5km hex grid).
+
+Downloads the GB-Hex-5km-GeoSure dataset from Ordnance Survey as an ESRI
+Shapefile and extracts it.
+
+Source: https://osdatahub.os.uk/downloads/open/GeoSure
+License: Open Government Licence v3.0
+"""
+
+import argparse
+import tempfile
+from pathlib import Path
+
+from pipeline.utils import download, extract_zip
+
+URL = "https://api.os.uk/downloads/v1/products/GB-Hex-5km-GeoSure/downloads?area=GB&format=ESRI%C2%AE+Shapefile&redirect"
+
+
+def main() -> None:
+    parser = argparse.ArgumentParser(
+        description="Download OS GeoSure ground stability data"
+    )
+    parser.add_argument(
+        "--output",
+        type=Path,
+        required=True,
+        help="Output directory for extracted shapefile",
+    )
+    args = parser.parse_args()
+
+    with tempfile.TemporaryDirectory() as cache_dir:
+        zip_path = Path(cache_dir) / "geosure.zip"
+
+        download(URL, zip_path, timeout=300)
+        extract_zip(zip_path, args.output)
+
+        shp_files = list(args.output.rglob("*.shp"))
+        print(f"Extracted {len(shp_files)} shapefiles to {args.output}")
+        for f in shp_files:
+            print(f"  {f.relative_to(args.output)}")
+
+
+if __name__ == "__main__":
+    main()