ci: consolidate platform pipelines and test prerequisites on macOS support

MeetingAssistant/MacOs/MacOsDesktopControlService.cs

@@ -33,7 +33,13 @@ public sealed class MacOsDesktopControlService : IHostedService, IDisposable
             return Task.CompletedTask;
         }
 
-        var helperPath = Path.Combine(AppContext.BaseDirectory, "Native", "macos-desktop-controls");
+        var helperPath = Path.Combine(
+            AppContext.BaseDirectory,
+            "Native",
+            "MeetingAssistantDesktopControls.app",
+            "Contents",
+            "MacOS",
+            "macos-desktop-controls");
         if (!File.Exists(helperPath))
         {
             logger.LogWarning("macOS desktop controls helper was not found at {HelperPath}", helperPath);