v0.5.0

Changed

• ContactData.phoneNumbers and ContactData.emailAddresses are now optional,
  like every other multi-entry field: a contact reachable only by DID has
  neither, and should not have to carry an empty array to say so.
  isContactData accepts them absent (still rejecting a present-but-malformed
  array), and normalizeContact is unchanged -- it keeps emitting [] for
  both, so its output stays byte-identical. Consumers that read either field
  without a ?? [] guard need updating.