Finished database management and user authentication

HopFrame.Database/Models/User.cs

@@ -0,0 +1,9 @@
+namespace HopFrame.Database.Models;
+
+public class User {
+    public Guid Id { get; set; }
+    public string Username { get; set; }
+    public string Email { get; set; }
+    public DateTime CreatedAt { get; set; }
+    public IList<string> Permissions { get; set; }
+}