Finished database management and user authentication

HopFrame.Database/Models/Entries/UserEntry.cs

@@ -0,0 +1,20 @@
+using System.ComponentModel.DataAnnotations;
+
+namespace HopFrame.Database.Models.Entries;
+
+public class UserEntry {
+    [Key, Required, MinLength(36), MaxLength(36)]
+    public string Id { get; set; }
+    
+    [MaxLength(50)]
+    public string Username { get; set; }
+    
+    [Required, MaxLength(50), EmailAddress]
+    public string Email { get; set; }
+    
+    [Required, MinLength(8), MaxLength(255)]
+    public string Password { get; set; }
+
+    [Required]
+    public DateTime CreatedAt { get; set; }
+}