fix command error output

[RacoonDog]

Replace usages of Text.toString() with Text.computeValue()

With test command /modmetadata (omitting argument to cause an error)

Current behaviour:

After changes:

[RickyTheRacc]

W

[RacoonDog]

(Before merging, I actually need to change it to use Text.asUnformattedString() instead of Text.computeValue(). Atm it doesn’t cause any issues as is, but who knows)

[thecatcore]

An additional review is needed here