swap webpacker for esbuild/jsbundling-rails

[Lordnibbler]

To run:

yarn build
rails s

# or
./bin/dev

Todo

• set up bin/dev
• is postcss set via postcss.config.js or via esbuild.config.js?
• get postcss/tailwindcss working with esbuild
• commented out stuff in PR
• does manifest.js need //= link_directory ../stylesheets .css?
• how to handle esbuild in test env
• config.assets in various config/environment files
• tailwind.config.js work-bg-light and work-bg-dark need url() paths that work
  • url('~images/home/experience-figure.svg') is how it used to be
  • need to combine postcss-import and postcss-url (https://github.com/postcss/postcss-url)
  • Referencing assets in CSS rails/cssbundling-rails#22
  • Manually resolved path in CSS url() evanw/esbuild#831
  • https://stackoverflow.com/questions/63658218/tailwind-css-backgroundimage-doesnt-work-for-me
  • alternatively, just use asset-path helpers and use inline styles instead of defining custom classes in tailwind
• blog page doesnt load
• delete app/javascript/packs/application.js in favor of app/javascript/application.js
• move javascripts in app/javascript/packs up one level
• .css files imported in photography.js fail to compile in esbuild
  • its looking for them in app/assets/packs instead of node_modules; perhaps an esbuild plugins issue (postCSS?)