WASM hello-world build (Emscripten)

engine/tests/wasm_hello.cpp

@@ -0,0 +1,18 @@
+#include <iostream>
+#include <emscripten/emscripten.h>
+
+extern "C" {
+
+// Exported function: add two numbers
+EMSCRIPTEN_KEEPALIVE
+int add(int a, int b) {
+    return a + b;
+}
+
+// Exported function: print hello message
+EMSCRIPTEN_KEEPALIVE
+void hello() {
+    std::cout << "Hello from C++ WASM!" << std::endl;
+}
+
+}