GuestLog - Localization - Initial Implementation

src/Somnia.GuestLog/Services/IDataListService.cs

@@ -0,0 +1,9 @@
+namespace Somnia.GuestLog.Services;
+
+public interface IDataListService
+{
+    public List<string> GetAvailableLists();
+    public HashSet<string> GetDataListByName(string dataListName);
+
+    public bool IsValueInList(string dataListName, string value);
+}