There is no chat command. You'd have to make one or find one already written.
The console command is 'connect <ip:<port if not default>>'
Though something like this idea would be a good way to learn lua, I don't understand why someone would wish to use it.
For the tiny bit of additional memory/server resources/filespace the command would take up for lua, it's easier to just use the console and use the already included in Source command.
