feat(algebra/order/group): some more lemmas about `min`, `max`, and `abs` (#16485)
feat(algebra/order/group): some more lemmas about `min`, `max`, and `abs` (#16485)

These are trivially true, but require a bit of annoying casework, making them handy to package into lemmas.





leanprover-community/mathlib,leanprover-community/mathlib