feat: add the option to use esbuild

[KonnorRogers]

Update by @jaredcwhite: focusing on esbuild initially, see below…

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Add a flag to use Snowpack and possibly other bundlers instead of webpack.

bridgetown new <dir> --bundler=snowpack

I'm thinking something like the syntax above.

Thoughts?

[jaredcwhite]

@ParamagicDev I like the concept…I'm not sure bundler by itself is quite the right term, it might be confusing as there's also Ruby Bundler. Maybe --frontend-bundler or something like that.

[jaredcwhite]

Starting to get excited about Snowpack/Skypack possibilities. Thinking this would be good to prioritize in Q1 2021. Also another opt idea: --frontend-builder=webpack, --frontend-builder=snowpack

[ayushn21]

Given that we have the --use-postcss option in main now and with the choice of frontend builders soon to come; I wonder if it's worth considering an interactive mode for bridgetown new? I know the number of options we have right now is pretty small, but as it gets bigger, it'll likely provide a better developer experience I reckon.

As a developer, I won't have to go through the docs and understsand which options are available to me beforehand. I could just run bridgetown new and be asked "How would you like to process your CSS?" and "Which frontend bundler would you like to use?".

I have no idea about the amount of work required for an interactive new command though and not completely sure if it's worth it at this point but thought I'd ask the question!!

[jaredcwhite]

I have a bit of experience now using esbuild, and with the recent update in Rails 7 to support esbuild specifically, I think it makes sense to focus on that for the time being.