fix(useRefHistory): clone lastRawValue for shouldCommit comparison

[meta-syntax]

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Description

Fixes #4985

shouldCommit receives same object reference for both oldValue and newValue when deep: true.
This is because lastRawValue holds direct reference to source.value.

Clone lastRawValue at 3 assignment sites using same clone logic as useManualRefHistory.

Added tests for shouldCommit + deep: true with object values (both sync and pre flush).

Additional context

[OrbisK]

maybe we should also clone the value here?

[meta-syntax]

Thank you for the review.
I agreed that it should be cloned for consistency. Updated.

[OrbisK]

we should clone it only once here. Clones can be costly.

[meta-syntax]

Thanks for catching this. Now cloning once and reusing it for both the shouldCommit check and the assignment.