mathlib

64283ce9 - feat(list/{zip,indexes}): Add `zip_with` and `map_with_index` lemmas (#5974)

feat(list/{zip,indexes}): Add `zip_with` and `map_with_index` lemmas (#5974) All proofs are due to @pechersky. Co-authored-by: Yakov Pechersky <ffxen158@gmail.com> Co-authored-by: Jannis Limperg <jannis@limperg.de>