Replace custom build scripts w/ Preconstruct

[chaance]

This PR replaces the current build scripts, which were forked and simplified based on tsdx, with Preconstruct. The tradeoffs of this change as I see it are:

Pros:

• Significantly faster build -- the entire repo builds in less than 20s now
• Similar build output -- we use almost exactly the same babel transforms as before, and preconstruct builds with rollup under the hood
• Less complexity to manage internally
• Some DX niceties to automate some tasks when creating new packages
• No more need for custom TS path aliases for each package (links for the dev env are created by preconstruct dev
• Preconstruct's source is familiar since it builds on top of rollup, so if we need to patch or fork for any reason it shouldn't be that scary

Cons:

• No more granular control over the build unless we want to fork the project
• Ummm...I think that's it?
• Really, pretty sure that's it

• Use a meaningful title for the pull request. Include the name of the package modified.
• Test the change in your own code (Compile and run).
• Add or edit tests to reflect the change (Run with yarn test).
• Add or edit Storybook examples to reflect the change (Run with yarn start).
• Ensure formatting is consistent with the project's Prettier configuration.
• Add documentation to support any new features.

This pull request:

• Creates a new package
• Fixes a bug in an existing package
• Adds additional features/functionality to an existing package
• Updates documentation or example code
• Other

[chaance]

@Andarist this change is inspired by your mentioning of this project at one point, so if you have any thoughts or suggestions for effectively working within Preconstruct's constraints I'd be glad to hear them. I've already found myself itching for a few things here that I can no longer access, but I'm trying to convince myself it isn't worth it 😛

[Andarist]

I like how you have summed up the cons If you ever find a need to fork - let's discuss it first :)

[Andarist]

maybe you would be willing to help with this issue: preconstruct/preconstruct#259 ? :>

[codesandbox-ci]

This pull request is automatically built and testable in CodeSandbox.

To see build info of the built libraries, click here or the icon next to each commit SHA.

Latest deployment of this branch, based on commit 4680d49:

Sandbox	Source
reach-ui-template	Configuration

[Andarist]

Excellent! Spread that Preconstruct love ❤️