Merge nucleic/warm-north-vole-pf37 into dev

NucleicApp/Services/RendererDispatcher.cs

@@ -0,0 +1,27 @@
+namespace NucleicApp.Services;
+
+/// Isolates WinUI's DispatcherQueue from the renderer state machine and keeps tests portable.
+public interface IRendererDispatcher
+{
+    void Post(Action action);
+}
+
+public sealed class SynchronizationContextDispatcher : IRendererDispatcher
+{
+    private readonly SynchronizationContext context;
+
+    public SynchronizationContextDispatcher(SynchronizationContext? context = null)
+    {
+        this.context = context ?? SynchronizationContext.Current
+            ?? throw new InvalidOperationException("renderer has no SynchronizationContext");
+    }
+
+    public void Post(Action action) => context.Post(static state => ((Action)state!).Invoke(), action);
+}
+
+public sealed class InlineRendererDispatcher : IRendererDispatcher
+{
+    public static InlineRendererDispatcher Instance { get; } = new();
+    private InlineRendererDispatcher() { }
+    public void Post(Action action) => action();
+}