Complete legacy operator UI and playout migration

MainWindow.Playout.cs

@@ -16,10 +16,15 @@ public sealed partial class MainWindow
     private readonly SemaphoreSlim _playoutCommandGate = new(1, 1);
     private IPlayoutEngine? _playoutEngine;
     private LegacyPlayoutWorkflow? _playoutWorkflow;
+    private PlayoutOptions? _playoutOptions;
+    private MutableLegacySceneCueCompositionOptionsSource? _legacyCompositionOptionsSource;
+    private LegacySceneCueCompositionOptions? _lastEnabledLegacyComposition;
     private string? _playoutInitializationError;
     private int _playoutCommandInFlight;
     private int _playoutShutdownStarted;
     private int _browserCorrelationQuarantined;
+    private int _operatorMutationQuarantined;
+    private string? _operatorMutationQuarantineMessage;
     private Task? _legacyRefreshTask;
     private readonly LegacyRefreshEpoch<LegacyRefreshRuntimeStatus> _legacyRefreshEpoch =
         new(LegacyRefreshRuntimeStatus.Empty);
@@ -30,6 +35,13 @@ public sealed partial class MainWindow
         {
             var options = PlayoutOptionsLoader.Load();
             var compositionOptions = PlayoutSceneCompositionFactory.Create(options);
+            _playoutOptions = options;
+            _legacyCompositionOptionsSource =
+                new MutableLegacySceneCueCompositionOptionsSource(compositionOptions);
+            _lastEnabledLegacyComposition = compositionOptions.BackgroundKind ==
+                LegacySceneBackgroundKind.None
+                ? null
+                : compositionOptions;
             _playoutEngine = PlayoutEngineFactory.Create(options);
             _playoutEngine.StatusChanged += OnPlayoutStatusChanged;
             if (_databaseRuntime is not null)
@@ -37,7 +49,9 @@ public sealed partial class MainWindow
                 _playoutWorkflow = LegacySceneRuntimeFactory.Create(
                     _playoutEngine,
                     _databaseRuntime.Executor,
-                    compositionOptions);
+                    compositionOptionsSource: _legacyCompositionOptionsSource,
+                    trustedManualSource: _manualNetSellStore,
+                    trustedViSource: _viManualListStore);
             }
         }
         catch (Exception exception)
@@ -1027,6 +1041,57 @@ public sealed partial class MainWindow
     private void ResetLegacyRefreshStatus() =>
         _legacyRefreshEpoch.Stop(_ => LegacyRefreshRuntimeStatus.Empty);
 
+    /// <summary>
+    /// Provides the single fail-closed playout boundary used by every operator-data
+    /// mutation. A missing engine/workflow is not an idle state: it means native
+    /// state cannot be proven, so a write must not start.
+    /// </summary>
+    private bool CanStartOperatorMutation(bool familyWriteQuarantined)
+    {
+        var engine = _playoutEngine;
+        var workflow = _playoutWorkflow;
+        var status = engine?.Status;
+        var workflowState = workflow?.State;
+        var refreshStatus = GetLegacyRefreshStatus();
+        var snapshot = new OperatorMutationGateSnapshot(
+            IsFamilyWriteQuarantined: familyWriteQuarantined,
+            IsGlobalWriteQuarantined: IsOperatorMutationQuarantined(),
+            IsLifetimeCancellationRequested: _lifetimeCancellation.IsCancellationRequested,
+            IsPlayoutCommandInFlight: Volatile.Read(ref _playoutCommandInFlight) != 0,
+            IsPlayoutShutdownStarted: Volatile.Read(ref _playoutShutdownStarted) != 0,
+            IsBrowserCorrelationQuarantined: IsBrowserCorrelationQuarantined(),
+            IsEngineAvailable: engine is not null,
+            IsWorkflowAvailable: workflow is not null,
+            IsCommandAvailable: status?.IsCommandAvailable ?? false,
+            IsPlayCompletionPending: status?.IsPlayCompletionPending ?? true,
+            PreparedSceneName: status?.PreparedSceneName,
+            OnAirSceneName: status?.OnAirSceneName,
+            PreparedCutCode: workflowState?.PreparedCutCode,
+            OnAirCutCode: workflowState?.OnAirCutCode,
+            IsRefreshActive: refreshStatus.IsActive,
+            IsRefreshTaskRunning: _legacyRefreshTask is { IsCompleted: false });
+
+        return OperatorMutationGate.CanStart(snapshot);
+    }
+
+    private bool IsOperatorMutationQuarantined() =>
+        Volatile.Read(ref _operatorMutationQuarantined) != 0;
+
+    private string GetOperatorMutationQuarantineMessage(string fallback) =>
+        Volatile.Read(ref _operatorMutationQuarantineMessage) ?? fallback;
+
+    private void LatchOperatorMutationQuarantine(string message)
+    {
+        if (Interlocked.CompareExchange(ref _operatorMutationQuarantined, 1, 0) == 0)
+        {
+            Volatile.Write(
+                ref _operatorMutationQuarantineMessage,
+                string.IsNullOrWhiteSpace(message)
+                    ? "An operator-data mutation has an unknown outcome. Restart and reconcile every operator-data store before writing again."
+                    : message);
+        }
+    }
+
     private void ShutdownPlayoutRuntime()
     {
         if (Interlocked.Exchange(ref _playoutShutdownStarted, 1) != 0)