hopefully not a horribly foolish refactoring

Femto.Modules.Authentication/Contracts/AuthenticationService.cs

@@ -0,0 +1,23 @@
+using Femto.Modules.Authentication.Data;
+using Femto.Modules.Authentication.Models;
+
+namespace Femto.Modules.Authentication.Contracts;
+
+internal class AuthenticationService(AuthenticationContext context) : IAuthenticationService
+{
+    public async Task<UserInfo> Register(string username, string password)
+    {
+        var user = new UserIdentity(username).WithPassword(password);
+        await context.AddAsync(user);
+        await context.SaveChangesAsync();
+
+        return new(user.Id, user.Username);
+    }
+
+    public async Task<UserInfo> Authenticate(string username, string password)
+    {
+        throw new NotImplementedException();
+    }
+}
+
+public class AuthenticationError(string message, Exception inner) : Exception(message, inner);