recaptcha: init support

packages/recaptcha/public/captcha-main.page.js

@@ -0,0 +1,18 @@
+(() => {
+    const { AutoloadPage } = window.Hydro;
+
+    const page = new AutoloadPage('recaptcha', () => {
+        function captcha(event) {
+            event.preventDefault();
+            grecaptcha.ready(function () {
+                grecaptcha.execute(UiContext.recaptchaKey, { action: 'submit' }).then(function (token) {
+                    document.getElementById('_captcha').value = token;
+                    document.getElementById('_submit').click();
+                });
+            });
+        }
+        document.getElementById('submit').onclick = captcha;
+    });
+
+    window.Hydro.extraPages.push(page);
+})();