support hot reloading content as data changes during development

[thescientist13]

Summary

Currently during development, Greenwood builds the list of all pages (the graph) including reading all frontmatter, and creates a data structure that it holds in memory, as well as outputting a graph.json file that can be read / fetched from userland.

However, this data / file never gets updated again, so if you change the frontmatter of a page, or add a new page, the content as data in your application will never change. Instead, you'll have to stop / start the dev server again to generate new data based on the new content.

Details

So naturally, we'll need to do a couple things to achieve this:

1. Be able to detect a content change (e.g. markdown / HTML) or at the very least tap into the livereload lifecycle and always generate new content as data
2. Output a new graph.json
3. Be able to globally update compilation.graph in-memory data structure
4. For GraphQL, would we have to hot-reload the entire server, or can we just have those resolvers resolve the content server, instead of graph.json