mathlib3

084f76e2 - feat(analysis/normed/group/add_circle): results about finite-order points on the circle (#17321)

feat(analysis/normed/group/add_circle): results about finite-order points on the circle (#17321) The main motivation for developing this API is the lemma `add_circle.le_add_order_smul_norm_of_is_of_fin_add_order` Co-authored-by: Eric Wieser <wieser.eric@gmail.com>