Add admin roles, user management, and campaign deletion

RpgRoller/Domain/GameModels.cs

@@ -19,9 +19,15 @@ public sealed class UserAccount
     public required string UsernameNormalized { get; init; }
     public required string PasswordHash { get; set; }
     public required string DisplayName { get; set; }
+    public required string Roles { get; set; }
     public Guid? ActiveCharacterId { get; set; }
 }
 
+public static class UserRoles
+{
+    public const string Admin = "admin";
+}
+
 public sealed class UserSession
 {
     public required string Token { get; init; }
@@ -42,7 +48,7 @@ public sealed class Character
 {
     public required Guid Id { get; init; }
     public required Guid OwnerUserId { get; set; }
-    public required Guid CampaignId { get; set; }
+    public Guid? CampaignId { get; set; }
     public required string Name { get; set; }
 }