build: onboarded to create-typescript-app (mostly)

[JoshuaKGoldberg]

Fixes #54.

Adds all the tooling from that template, except:

• Jest is still used for tests instead of Vitest to make that transition easier
• Babel is used for building to go along with ☝️ (https://github.com/egoist/tsup/issues/665)
• The output directory stays as dist/, not the template's default lib/
• https://github.com/JoshuaKGoldberg/sentences-per-line: as it conflicts with eslint-doc-generator

Adds an explicit "works with spaces" test alongside the existing "works with tabs" now that the repo is switched to tabs.

[github-actions[bot]]

:tada: This is included in version v1.5.2 :tada:

The release is available on:

• GitHub releases
• npm package (@latest dist-tag)

Cheers! 📦🚀