Under a full coverage run on every core, a test file's first cold import
(0.6-0.8 s alone) outran the 5 s case timeout and the half-done import
failed every later case in the file: the vitest lane went red in 2 of 5
runs with no defect. A beforeAll warm-up in the 4 files of that pattern;
5 of 5 full runs green after.