Migrate remaining legacy operator workflows

src/MBN_STOCK_WEBVIEW.Playout/Configuration/ValidatedPlayoutOptions.cs

@@ -15,6 +15,7 @@ internal sealed record ValidatedPlayoutOptions(
     int? OutputChannel,
     int LayoutIndex,
     string? SceneDirectory,
+    string? OperatorBackgroundDirectory,
     Regex? TestProcessWindowTitleRegex,
     IReadOnlySet<string> TestSceneAllowlist,
     bool TrustedLiveOutputEnabled,
@@ -59,6 +60,13 @@ internal sealed record ValidatedPlayoutOptions(
             sceneDirectory = ValidateSceneDirectory(options.SceneDirectory);
         }
 
+        var operatorBackgroundDirectory =
+            PlayoutSceneCompositionFactory.TryGetConfiguredBackgroundDirectory(
+                options,
+                out var configuredBackgroundDirectory)
+                ? configuredBackgroundDirectory
+                : null;
+
         RequireRange(options.QueueCapacity, 1, 4_096, nameof(options.QueueCapacity));
         RequireRange(
             options.ConnectTimeoutMilliseconds,
@@ -156,6 +164,7 @@ internal sealed record ValidatedPlayoutOptions(
             options.OutputChannel,
             options.LayoutIndex,
             sceneDirectory,
+            operatorBackgroundDirectory,
             titleRegex,
             allowlist,
             options.TrustedLiveOutputEnabled,
@@ -356,9 +365,14 @@ internal sealed record ValidatedPlayoutOptions(
                 return background;
             case PlayoutSetBackgroundTexture texture:
                 ValidateMutationTiming(texture.Timing);
-                return texture with { AssetPath = ResolveAssetPath(texture.AssetPath) };
+                ValidateAssetRoot(texture.AssetRoot);
+                return texture with
+                {
+                    AssetPath = ResolveAssetPath(texture.AssetPath, texture.AssetRoot)
+                };
             case PlayoutSetBackgroundVideo video:
                 ValidateMutationTiming(video.Timing);
+                ValidateAssetRoot(video.AssetRoot);
                 // The legacy MainForm intentionally uses 2004 for the common studio
                 // background. Keep the input bounded while retaining that vendor value.
                 if (video.LoopCount is < 0 or > 10_000)
@@ -366,16 +380,28 @@ internal sealed record ValidatedPlayoutOptions(
                     throw new PlayoutRequestException("장면 배경 영상 반복 값이 올바르지 않습니다.");
                 }
 
-                return video with { AssetPath = ResolveAssetPath(video.AssetPath) };
+                return video with
+                {
+                    AssetPath = ResolveAssetPath(video.AssetPath, video.AssetRoot)
+                };
             default:
                 throw new PlayoutRequestException("지원하지 않는 장면 변경 항목입니다.");
         }
     }
 
     private string ResolveAssetPath(string? relativePath)
+        => ResolveAssetPath(relativePath, PlayoutAssetRoot.SceneDirectory);
+
+    private string ResolveAssetPath(string? relativePath, PlayoutAssetRoot assetRoot)
     {
         relativePath = relativePath?.Trim();
-        if (SceneDirectory is null || string.IsNullOrEmpty(relativePath) ||
+        var root = assetRoot switch
+        {
+            PlayoutAssetRoot.SceneDirectory => SceneDirectory,
+            PlayoutAssetRoot.OperatorBackgroundDirectory => OperatorBackgroundDirectory,
+            _ => null
+        };
+        if (root is null || string.IsNullOrEmpty(relativePath) ||
             Path.IsPathRooted(relativePath) || relativePath.Contains("..", StringComparison.Ordinal) ||
             relativePath.Any(char.IsControl))
         {
@@ -393,12 +419,28 @@ internal sealed record ValidatedPlayoutOptions(
             throw new PlayoutRequestException("지원하지 않는 장면 자산 형식입니다.");
         }
 
-        var candidate = Path.GetFullPath(Path.Combine(SceneDirectory, relativePath));
-        var rootPrefix = SceneDirectory.EndsWith(Path.DirectorySeparatorChar)
-            ? SceneDirectory
-            : SceneDirectory + Path.DirectorySeparatorChar;
+        if (assetRoot == PlayoutAssetRoot.OperatorBackgroundDirectory)
+        {
+            try
+            {
+                return TrustedPlayoutAssetPath.ResolveRelativeFile(
+                    root,
+                    relativePath,
+                    new HashSet<string>(allowedExtensions, StringComparer.OrdinalIgnoreCase));
+            }
+            catch (TrustedPlayoutAssetException)
+            {
+                throw new PlayoutRequestException(
+                    "신뢰 배경 파일을 확인할 수 없습니다.");
+            }
+        }
+
+        var candidate = Path.GetFullPath(Path.Combine(root, relativePath));
+        var rootPrefix = root.EndsWith(Path.DirectorySeparatorChar)
+            ? root
+            : root + Path.DirectorySeparatorChar;
         if (!candidate.StartsWith(rootPrefix, StringComparison.OrdinalIgnoreCase) ||
-            !File.Exists(candidate) || HasReparsePointBetween(SceneDirectory, candidate))
+            !File.Exists(candidate) || HasReparsePointBetween(root, candidate))
         {
             throw new PlayoutRequestException("허용된 장면 자산을 찾을 수 없습니다.");
         }
@@ -469,6 +511,14 @@ internal sealed record ValidatedPlayoutOptions(
         }
     }
 
+    private static void ValidateAssetRoot(PlayoutAssetRoot assetRoot)
+    {
+        if (!Enum.IsDefined(assetRoot))
+        {
+            throw new PlayoutRequestException("배경 자산 루트가 올바르지 않습니다.");
+        }
+    }
+
     private static bool IsByte(int value) => value is >= byte.MinValue and <= byte.MaxValue;
 
     private static bool CanMatchProgramTitle(Regex regex)