feat(category_theory/monad): monadic adjunctions (#1176)
* feat(category_theory/limits): equivalences create limits
* equivalence lemma
* feat(category_theory/monad): monadic adjunctions
* move file
* fix
* add @[simp]
* use right_adjoint_preserves_limits
* fix
* fix
* undo weird changes in topology files
* formatting
* do colimits too
* missing proofs
* convert monad to a typeclass decorating a functor
* changing name
* cleaning up
* oops
* minor