Split out event type SIGs, and do other enum conversions. Closes #138

data/sig_ref.py

@@ -1,5 +1,7 @@
 from dataclasses import dataclass
 
+from core.enums import SIGRefType
+
 
 @dataclass
 class SIGRef:
@@ -13,7 +15,7 @@ class SIGRef:
     # Name of the reference, e.g. "Null Country Park", if known.
     name: str | None = None
     # Type of the reference, e.g. "Park", if known.
-    ref_type: str | None = None
+    ref_type: SIGRefType = SIGRefType.UNKNOWN
     # URL to look up more information about the reference, if known.
     url: str | None = None
     # Latitude of the reference, in degrees, if known.