[proposal] re-evaluate testing tools

[DRiFTy17]

Proposal

We currently utilize Karma and Jasmine for unit tests. This works, but is slow and the tests become hard to maintain. These tools are outdated, but mature. We have also found that certain tests are flaky, partly due to our implementation, but also due to the tools we have at our disposal. We should evaluate more modern tools such as web-test-runner and Playwright for improved testing practices and stability.

At the time of writing, web-test-runner or Vitest would work very well

Affected components

Only affects tests, not components, but our test suite is large.

Benefits

• Improved test run performance
• Improved test stability
• Improved test maintenance
• Forces us to rethink how we write our tests

Combined with the architectural proposal, our tests could be more focused.

Caveats

• Refactor full test suite
• Likely rewrite a lot of tests from the ground up