Fixed: Storage.File no longer discards a valid creds.term as corrupt on a cold
start (#1).

Added: reply/mentions, poll votes, pin/keep, view-once/PTV, group-invite
messages, events, albums, and receive-side classification of more inbound types.

Changed (breaking): reaction/edit/revoke/poll-vote take a message_ref
(%Amarula.Msg{} or {jid, msg_id}) instead of a raw %Proto.MessageKey{}.