test: Introduce visual regression tests using Playwright

[gnapse]

Short description

Work in progress.

See https://twist.com/a/1585/ch/607587/t/3963022/

PR Checklist

• Added tests for bugs / new features
• Updated docs (storybooks, readme)
• Executed npm run validate and made sure no errors / warnings were shown
• Described changes in CHANGELOG.md
• Bumped version in package.json and package-lock.json (npm --no-git-tag-version version <major|minor|patch>) ref
• Updated all static build artifacts (npm run build-all)

Versioning

[gnapse]

Something introduced in this PR has broken the tsdx build command. I noticed first on CI, but when I run it locally I can reproduce. To do so, run this command locally:

tsdx build --tsconfig tsconfig.dist.json

The closest I've found online related to the error message is rollup/rollup#3591. Maybe tsdx is using a rollup version older than the one in which a fix for that issue was released. Meaning we really need to get rid of tsdx soon.

[henningmu]

Maybe tsdx is using a rollup version older than the one in which a fix for that issue was released

According to package-lock, tsdx is using 2.79.1. The fix went live with 2.11.0. Must be something else 😞

Meaning we really need to get rid of tsdx soon

This is true regardless, and might be the easier solution than figuring out the root cause here 😅