Update tag-based parsing to use lambda for additional customization

[matthchr]

This allows callers to override a bit more about struct field parsing. In particular, it's useful when parsing tags to perform escaping of tags that aren't supported CEL field names.
This allows implementation of something similar to what Kuberentes does with CEL field names:
https://kubernetes.io/docs/reference/using-api/cel/#escaping.

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[matthchr]

Realized this might be somewhat related to #1002

[matthchr]

My main use-case for this is to control escaping of tags that aren't valid CEL names, but there are probably other viable use-cases as well like conditionally adding field name suffixes/prefixes or similar. Felt like rather than try to encode everything in the native types handler just exposing a function that enabled the caller to configure it how they want made sense.

[TristonianJones]

/gcbrun