feat: playlist implementation

octo-fiesta/Models/Subsonic/ExternalPlaylist.cs

@@ -0,0 +1,58 @@
+namespace octo_fiesta.Models.Subsonic;
+
+/// <summary>
+/// Represents a playlist from an external music provider (Deezer, Qobuz).
+/// </summary>
+public class ExternalPlaylist
+{
+    /// <summary>
+    /// Unique identifier in the format "pl-{provider}-{externalId}"
+    /// Example: "pl-deezer-123456" or "pl-qobuz-789"
+    /// </summary>
+    public string Id { get; set; } = string.Empty;
+    
+    /// <summary>
+    /// Playlist name
+    /// </summary>
+    public string Name { get; set; } = string.Empty;
+    
+    /// <summary>
+    /// Playlist description
+    /// </summary>
+    public string? Description { get; set; }
+    
+    /// <summary>
+    /// Name of the playlist creator/curator
+    /// </summary>
+    public string? CuratorName { get; set; }
+    
+    /// <summary>
+    /// Provider name ("deezer" or "qobuz")
+    /// </summary>
+    public string Provider { get; set; } = string.Empty;
+    
+    /// <summary>
+    /// External ID from the provider (without "pl-" prefix)
+    /// </summary>
+    public string ExternalId { get; set; } = string.Empty;
+    
+    /// <summary>
+    /// Number of tracks in the playlist
+    /// </summary>
+    public int TrackCount { get; set; }
+    
+    /// <summary>
+    /// Total duration in seconds
+    /// </summary>
+    public int Duration { get; set; }
+    
+    /// <summary>
+    /// Cover art URL from the provider
+    /// </summary>
+    public string? CoverUrl { get; set; }
+    
+    /// <summary>
+    /// Playlist creation date
+    /// </summary>
+    public DateTime? CreatedDate { get; set; }
+}