[DAG] foldABSToABD - support abs(*ext(x) - *ext(y)) -> zext(abd*(x, y)) from...

[DAG] foldABSToABD - support abs(*ext(x) - *ext(y)) -> zext(abd*(x, y)) from different extension source types (#71670)

We currently limit the fold to cases where we're extending from the same source type, but we can safely perform this using the wider of mismatching source types (we're really just interested in having extension bits on both sources), ensuring we don't create additional extensions/truncations.