Add Card solver to bags (#7986)

Add Card solver to bags (#7986)

This PR avoids reducing bag.card terms with quantifiers unless it is needed.
It does so by building a cardinality graph for bags and adds appropriate constraints on internal nodes in the graph and min size constraints for the leaves.
This works for many of the benchmarks where each internal node has a single set of children.
Reduction lemmas are only generated when there are multiple sets of children.
Cardinality for bag.difference_remove and bag.duplicate_removal is not supported and would handled in future PR