Add fail-closed regional detector routing

tests/test_evaluate_belgium_building_candidate.py

@@ -0,0 +1,23 @@
+from pathlib import Path
+
+import pytest
+
+from scripts.evaluate_belgium_building_candidate import parse_regional_models
+
+
+def test_parse_regional_models_accepts_explicit_unique_routes() -> None:
+    assert parse_regional_models(["flanders=/models/flanders.pt", "wallonia=/models/wallonia.pt"]) == {
+        "flanders": Path("/models/flanders.pt"),
+        "wallonia": Path("/models/wallonia.pt"),
+    }
+
+
+@pytest.mark.parametrize("value", ["flanders", "=/model.pt", "flanders="])
+def test_parse_regional_models_rejects_incomplete_routes(value: str) -> None:
+    with pytest.raises(ValueError, match="expected REGION"):
+        parse_regional_models([value])
+
+
+def test_parse_regional_models_rejects_duplicate_routes() -> None:
+    with pytest.raises(ValueError, match="Duplicate regional model"):
+        parse_regional_models(["flanders=/first.pt", "FLANDERS=/second.pt"])