bun test

bun test vs Vitest: 136ms vs 1.67s on 300 Tests

bun test 1.4.2 vs Vitest 5.0.3 on 300 TypeScript tests in 60 files: warm wall medians 136 ms vs 1,673 ms (~12x); Vitest --no-isolate 765 ms (~5.6x). A 5-file vitest-API check (vi.fn, vi.mock, fake timers, spyOn, it.each, snapshot) passed 7/7 under Bun.