chore(gpui): vendor the experimental native runtime

vendor/react-native-gpui/packages/cli/templates/modules/cpp/RNModule.cpp

@@ -0,0 +1,29 @@
+#include "RNModule.hpp"
+
+#include <RNModuleSpec.h>
+
+#include <memory>
+#include <string>
+#include <utility>
+
+namespace {
+namespace jsi = facebook::jsi;
+using facebook::react::CallInvoker;
+using facebook::react::TurboModule;
+
+class RNModule final : public facebook::react::NativeModuleSpec<RNModule> {
+ public:
+  explicit RNModule(std::shared_ptr<CallInvoker> jsInvoker)
+      : NativeModuleSpec(std::move(jsInvoker)) {}
+
+  std::string greet(jsi::Runtime&, std::string name) {
+    return "Hello from C++, " + name + "!";
+  }
+};
+} // namespace
+
+std::shared_ptr<TurboModule> create_rn_module(
+    const std::string& name,
+    std::shared_ptr<CallInvoker> jsInvoker) {
+  return rngpui::provideTurboModule<RNModule>(name, std::move(jsInvoker));
+}