chore: import MusifyBackend into monorepo (preserving history)

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

MusifyBackend/Application/Tracks/Commands/DeleteTrackCommand.cs

@@ -0,0 +1,10 @@
+using Ardalis.Result;
+using Mediator;
+
+namespace Musify.Application.Tracks.Commands
+{
+    public record DeleteTrackCommand(
+        long UserId,
+        Guid TrackId)
+        : ICommand<Result>;
+}