Add Tonuino Manager website and Sparkle updates

Sources/TonuinoManager/Models/LibraryModels.swift

@@ -0,0 +1,34 @@
+import Foundation
+
+struct MusicFolder: Identifiable, Hashable, Sendable {
+    let number: Int
+    let url: URL
+    var tracks: [MusicTrack]
+    var customName: String? = nil
+    var id: Int { number }
+    var title: String { customName ?? tracks.first(where: { !$0.album.isEmpty })?.album ?? "Ordner \(String(format: "%02d", number))" }
+}
+
+struct MusicTrack: Identifiable, Hashable, Sendable {
+    let url: URL
+    var title: String
+    var artist: String
+    var album: String
+    var albumArtist: String = ""
+    var trackNumber: String = ""
+    var discNumber: String = ""
+    var year: String = ""
+    var genre: String = ""
+    var acoustID: String = ""
+    var musicBrainzRecordingID: String = ""
+    var musicBrainzReleaseID: String = ""
+    var id: String { url.path }
+    var displayTitle: String { title.isEmpty ? url.deletingPathExtension().lastPathComponent : title }
+}
+
+struct SystemMusicFolder: Identifiable, Hashable, Sendable {
+    let name: String
+    let url: URL
+    var tracks: [MusicTrack]
+    var id: String { name }
+}