Commit f03b104de5

Remove unused vitest tooling instead of bumping it

There are no tests and no vitest config — the only greps that looked
like usage were substrings of `submit(` and `split(`. The dependency
was carrying real cost for that:

- every one of the 9 reported vulnerabilities (1 critical, 4 high, 4
  moderate) came from this chain: vitest, @vitest/mocker, vite,
  vite-node, esbuild, miniflare, ws, @cloudflare/vitest-pool-workers
- the lockfile shrinks from 4,583 to 1,641 lines once the esbuild,
  sharp, and workerd platform binaries go with it
- it was generating recurring Dependabot churn for a test runner that
  never runs

`npm audit` now reports 0 vulnerabilities. Type checking and the
Worker bundle are unaffected, since nothing imported it.

Also drops the dead `test` script. Add both back, at whatever version
is current, alongside the first actual test.

Layout: unified · split