build: bundle render worker/backends and fix concurrent param test

- Make olive-editor depend on olive-render-worker on all platforms so the
  worker is always built with the main app.
- Copy olive-render-worker and dynamic render backends (oakgl, oakvulkan)
  into the macOS app bundle next to the executable.
- Include oakgl.dll and oakvulkan.dll in the Windows NSIS installer.
- Fix PluginSmokeThread.ConcurrentParamAccess CI failure by adding a mutex
  around IntegerInstance's no-node fallback storage and serializing the
  test's set/get pair.
- Hide the render worker's Dock icon on macOS via
  NSApplicationActivationPolicyProhibited.

app/render/worker/workermain.cpp

@@ -51,6 +51,10 @@
 #include "render/colorprocessor.h"
 #include "render/colortransform.h"
 
+#ifdef Q_OS_MACOS
+void HideWorkerDockIcon();
+#endif
+
 namespace
 {
 
@@ -520,6 +524,11 @@ int main(int argc, char *argv[])
 	InstallSurfaceFormat();
 
 	QGuiApplication app(argc, argv);
+
+#ifdef Q_OS_MACOS
+	HideWorkerDockIcon();
+#endif
+
 	QCoreApplication::setOrganizationName(QStringLiteral("oakvideoeditor.org"));
 	QCoreApplication::setApplicationName(QStringLiteral("olive-render-worker"));