Fix regex dos

[IceTank]

I think this should fix the regex dos. I am not sure if all types of whispers and chat messages still work. Might have to see if people report issues.

[rom1504]

let's do that first PrismarineJS/prismarine-chat#51

[Chitasa]

Seems to fail on the cases where prefix is longer than 5 characters https://regex101.com/r/OhOJIM/5
You can probably instead use lazy matching (ex: (?:\(.+?\)|\[.+?\]|.)*?(\w{3,16}))