Add hydrate support

Author: justinfagnani

packages/site-client/src/entrypoints/hydrate.ts

@@ -0,0 +1,7 @@
+/**
+ * @license
+ * Copyright 2022 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import 'lit/experimental-hydrate-support.js';

packages/site-server/src/catalog/routes/element/element-route.ts

@@ -81,6 +81,7 @@ export const handleElementRoute = async (
   context.body = Readable.from(renderPage({
     title: `${packageName}/${elementName}`,
     scripts: [
+      '/js/hydrate.js',
       '/js/element.js'
     ],
     content: render(