feat: migrate legacy playout workflow and scenes

src/MBN_STOCK_WEBVIEW.Playout/Configuration/PlayoutOptions.cs

@@ -1,4 +1,5 @@
 using MBN_STOCK_WEBVIEW.Core.Playout;
+using MBN_STOCK_WEBVIEW.Core.Playout.Scenes;
 
 namespace MBN_STOCK_WEBVIEW.Playout.Configuration;
 
@@ -20,6 +21,22 @@ public sealed class PlayoutOptions
 
     public int LayoutIndex { get; set; } = 10;
 
+    /// <summary>MainForm ComboDi.SelectedIndex default passed to SetSceneEffectType.</summary>
+    public int LegacySceneFadeDuration { get; set; } = 6;
+
+    /// <summary>
+    /// Trusted MainForm-level background selection. The asset is always a path relative
+    /// to SceneDirectory and is never accepted from Web content.
+    /// </summary>
+    public LegacySceneBackgroundKind LegacySceneBackgroundKind { get; set; } =
+        LegacySceneBackgroundKind.None;
+
+    public string? LegacySceneBackgroundAssetPath { get; set; }
+
+    public int LegacySceneBackgroundVideoLoopCount { get; set; } = 2004;
+
+    public bool LegacySceneBackgroundVideoLoopInfinite { get; set; } = true;
+
     /// <summary>
     /// External absolute root containing vendor .t2s scenes. Required in Test and Live modes.
     /// </summary>
@@ -27,6 +44,10 @@ public sealed class PlayoutOptions
 
     public string? TestProcessWindowTitlePattern { get; set; }
 
+    /// <summary>
+    /// Closed scene-name allowlist for every real Test or Live output command.
+    /// The property name is retained for existing local configuration files.
+    /// </summary>
     public List<string> TestSceneAllowlist { get; set; } = [];
 
     public bool TrustedLiveOutputEnabled { get; set; }