* core: member mentions, types and rfc
* update
* update rfc
* save/get mentions (WIP)
* markdown
* store received mentions and userMention flag
* sent mentions
* update message with mentions
* db queries
* CLI mentions, test passes
* use maps for mentions
* tests
* comment
* save mentions on sent messages
* postresql schema
* refactor
* M.empty
* include both displayName and localAlias into MentionedMemberInfo
* fix saving sent mentions
* include mentions in previews
* update plans
* core: profile names with spaces
* test
* more test
* update name validation, export C API
* refactor
* validate name when creating profile in CLI
* validate display name in all APIs when it is changed