typescript-node: Fix yarn lockfile, test value, and script/test for CI

[adamnfish-gu]

The project had a Yarn Classic v1 yarn.lock alongside a .yarnrc.yml configured for Yarn Berry and a .yarn/install-state.gz. The sibling javascript and javascript-esm projects both use Yarn Berry 3.

Deletes the v1 yarn.lock and regenerates it with Yarn 3.8.7. Adds a packageManager field to package.json to pin the choice.

myConst was false while the test expected true; it now returns true. script/test ran yarn test --watch, which never exits. It now runs once, with the watch loop behind --watch.

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Base platform/tool-versions-ci (#144), so the diff shows only this branch's changes. Merge #144 first.

Part of #143.

[bryophyta]

As mentioned in the corresponding JS PR I suspect that the test was failing intentionally, but as long as the change to a passing test is intentional then this looks good to me 👍

[adamnfish-gu]

I suspect that the test was failing intentionally

For sure! The original pattern was to have a failing test in every project skeleton, I guess to follow the TDD pattern of going red -> green in a loop.

We've different priorities with this new layout. Because we want to catch problems with these ill-maintained examples, we need a way to automatically verify that the setup works. The fact that we had a test suite already in each skeleton means that's a great way to do it.

We don't lose much (if anything) on the getting started side by having the test start green, but we gain a lot on the maintenance side by having these tests be automatically checked.

This is why each language is split into two PRs - one to set up the project (including making sure the test suite passes), and a second one that migrates to the new .tool-versions file structure. I'm happy to combine them all into one PR each if we think that would be clearer, but I do find it much easier to review a single tightly focused PR and this is especially important when there are quite a few of them.

Thanks for taking a look!