chore: import MusifyBackend into monorepo (preserving history)

git-subtree-dir: MusifyBackend
git-subtree-mainline: 6829e769ed
git-subtree-split: ed7b00c2cc

MusifyBackend/Domain/Entities/UserHasTrack.cs

@@ -0,0 +1,24 @@
+using System.ComponentModel.DataAnnotations;
+using System.ComponentModel.DataAnnotations.Schema;
+
+namespace Musify.Domain.Entities
+{
+#pragma warning disable CS8618
+    [Table("UserHasTrack")]
+    public class UserHasTrack
+    {
+        public Guid Id { get; set; } = Guid.NewGuid();
+
+        [Required]
+        public required long UserId { get; set; }
+
+        [Required]
+        public required Guid TrackId { get; set; }
+
+        [ForeignKey(nameof(UserId)) ]
+        public User User { get; set; }
+
+        [ForeignKey(nameof(TrackId)) ]
+        public Track Track { get; set; }
+    }
+}