Adds support for a Lit renderer (#665)

* Adds support for a Lit renderer

This adds `@astrojs/renderer-lit`. An experimental Lit renderer.

* Removed cached submodule, mistake

* Prevent globals clobbering

* Add docs on globals

1 files changed, 19 insertions, 0 deletions

diff --git a/packages/renderers/renderer-lit/index.js b/packages/renderers/renderer-lit/index.js
new file mode 100644
index 000000000..38b59a6f7
--- /dev/null
+++ b/packages/renderers/renderer-lit/index.js
@@ -0,0 +1,19 @@
+export default {
+  name: '@astrojs/renderer-lit',
+  server: './server.js',
+  external: [
+    '@lit-labs/ssr/lib/install-global-dom-shim.js',
+    '@lit-labs/ssr/lib/render-lit-html.js',
+    '@lit-labs/ssr/lib/lit-element-renderer.js'
+  ],
+  polyfills: [
+    './client-shim.js'
+  ],
+  hydrationPolyfills: [
+    'lit/experimental-hydrate-support.js'
+  ],
+  knownEntrypoints: [
+    '@astrojs/renderer-lit/client-shim.js',
+    '@webcomponents/template-shadowroot/template-shadowroot.js'
+  ]
+};