Description

• Closes Vitest 4 can no longer have projects with import ... 'bun' #9257

I added a test case to verify #9257 is fixed on Vite 8.

I also added a test case to show manual mocking still transforms the original module. I dug a bit and I'm not sure yet if I can fix it yet or intended behavior, so I just added a test for this. Will create a separate issue for this and discuss.

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