This changes all hmx files to astro files and updates all code to not reference hmx any more.
* Add support for React components. This adds support for react components via a new `extensions` config in astro.config.mjs. In the future we can extend this to do things like look at the import statements, as Snowpack does. * Fix the tests
* Inject styling in HTML AST * Restore optimize structure
* Add style transforms * Let crawler be sync
