Also added forgotten default for `discordbancommand` + new switch syntax.
* Add `null` check if member is invalid.
* Make meta sound more correct.
* Meta optimization + another `discordban` optimization
Thanks to Funky on discord for suggesting the meta change (https://discord.com/channels/315163488085475337/1027064108056580106/1065251950268010567). (commit: 4097373)
