fix(jest-mock): restore withImplementation after errors

[fallintoplace]

Summary

Fixes mockFn.withImplementation(...) so it restores the previous mock state when the callback throws synchronously or rejects asynchronously.

Closes #16218.

Motivation

withImplementation is documented as a temporary override, but the current implementation only restores state on the normal synchronous path and on fulfilled promises. That leaves the temporary implementation installed after exceptional exits.

How this works

• restore the previous mock state in a shared helper
• restore immediately when the callback throws
• adopt thenables through the environment Promise and restore on both fulfillment and rejection
• add regressions for sync throws and async rejections, including restoration of queued mockImplementationOnce state and whenCalledWith fallback behavior

Validation

• yarn jest packages/jest-mock/src/__tests__/index.test.ts --runInBand
• yarn jest packages/jest-mock/src/__tests__ --runInBand
• yarn build:ts
• yarn typecheck:tests

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