feat: Introduce %$ option to add number of the test to its title

[kemuridama]

Description

Jest v30 planned to introduce %$ option which adds the number of the test to its title within each() method by jestjs/jest#14710. This PR imports this feature into Vitest.

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Tests

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[kemuridama]

@hi-ogawa Thank you for your review. I think I probably resolved your feedbacks.

[hi-ogawa]

Looks good!