[Variant] Make VariantArray iterable #8612
Description
Is your feature request related to a problem or challenge? Please describe what you are trying to do.
Currently, there is no way to safely iterate over VariantArray. Only VariantArray::value(i) is available, which panics on null values.
Additional context
This feature is motivated by datafusion-variant, a higher-level library that integrates with Datafusion through a series of udfs