Persist backend state with EF Core SQLite

RpgRoller/Domain/GameModels.cs

@@ -16,8 +16,10 @@ public sealed class UserAccount
 {
     public required Guid Id { get; init; }
     public required string Username { get; init; }
+    public required string UsernameNormalized { get; init; }
     public required string PasswordHash { get; set; }
     public required string DisplayName { get; set; }
+    public Guid? ActiveCharacterId { get; set; }
 }
 
 public sealed class UserSession