Clear and concise description of the problem

The useIDBKeyval integration is great, but I was suprised that there was no way to customise the serialization on write/read.

Suggested solution

It would be good to bring it up to parity with the regular useStorage, as per https://vueuse.org/core/useStorage/#custom-serialization

Alternative

No response

Additional context

No response

Validations

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