refactor: migrate tests to Vitest + TS

[jescalada]

Fixes #1150, built on top of #1166.

Not all tests were perfectly refactored from Chai/Mocha -> Vitest. Some required partial or total rewriting to get them to play nice.

Some tests, specifically the proxy-related tests (proxy.test.ts, testProxy.test.ts and most importantly testProxyRoute.test.ts) have been very problematic for some reason - the tests in testPush.test.ts seem to fail in the CI when some of the proxy tests execute prior. They fail on the first execution locally, and then pass without issue (maybe a caching/cleanup problem).

Coverage has dropped somewhat to 80.5%, but we should see an increase after removing unused/untested code such as plugin stuff.

Note that the CI is failing due to the new Blue Oak license.

[jescalada]

@kriswest I think this is ready for another look - hoping to get the v2 release ready soon!

[kriswest]

LGTM - thanks for the logging cleanup and email comparison fix. Still had a couple of type overrides I wasn't sure you needed... worth leaving a comment if it is needed.

The only lingering issue I see is the proxy tests. Logging errors on start/stop might be worth doing (as it appears not to have stopped...). If that doesn't turn up the answer then it should go on an issue so we can get this merged.

[jescalada]

@kriswest Thanks for taking another look! Hoping it's ready to go now 😃

[coopernetes]

Just a few misc comments. With all the tests passing in CI and using all the vitest mocking facilities, this overall LGTM. Note I didn't do a fine grained review.

A few things we can track in separate issues related to e2e testing, integration testing and removing some of the weird test setups where shared state is making these layers difficult to test. I would also recommend splitting up the Express app layers so that they can import each other & more easily be mocked.