SmrPlayer: return message_id of sent messages
SmrPlayer: return message_id of sent messages

This will allow us to keep track of `message_id` for some places
that may need it (e.g. canceling alliance invitations).

smrealms/smr,smrealms/smr,hemberger/smr,hemberger/smr,hemberger/smr,smrealms/smr,hemberger/smr