Add playwright E2E tests (#2174)

photon-client/tests/global-setup.ts

@@ -0,0 +1,7 @@
+async function globalSetup() {
+  // You can perform global setup tasks here, such as starting a server or setting environment variables
+  const path = await import("path");
+  process.env.TESTS_DIR = path.resolve(process.cwd());
+}
+
+export default globalSetup;