feat(client): revamp CfgUser

feat(client): change api_server to server_address in CfgDev

chore: update copyright notices

chore(client): rename sdbclient to client

chore(sdbclient): cleanup some old comments

Finish register/login, load configs on startup

Change CfgHidden to CfgDev

Constants for Cfg filenames

Serde for Cfg structs

Serde for Cfg structs

New CfgUser fields

Add ProjectDirs resource

Move Cfg things to a new mod