Implemented Login workflow

SpotiParty.Web/Models/User.cs

@@ -0,0 +1,14 @@
+using System.ComponentModel.DataAnnotations;
+
+namespace SpotiParty.Web.Models;
+
+public class User {
+    [Key]
+    public Guid UserId { get; init; } = Guid.CreateVersion7();
+    
+    [MaxLength(255)]
+    public string DisplayName { get; init; }
+    
+    [MaxLength(255)]
+    public string RefreshToken { get; set; }
+}