[Embeds] Create vite project and add to build pipeline (#3448)

* add bskyembed vite app

* create build script (temp until embedr is ready)

Dockerfile

@@ -32,7 +32,8 @@ RUN \. "$NVM_DIR/nvm.sh" && \
   npm install --global yarn && \
   yarn && \
   yarn intl:build && \
-  yarn build-web
+  yarn build-web && \
+  yarn build-embed
 
 # DEBUG
 RUN find ./bskyweb/static && find ./web-build/static