[FEATURE REQUEST] do not use the same exit code for different events

[phpmoli]

Hello,

Problem: i am using steamctl in a batch program, in case of errors, so far i only/always got exit code value 1, what means i can not handle errors without parsing language/translation-specific-free-text stderr.

Solution: use different exit codes for every single error type: if the error text would change, change the exit code too. Reading the steamctl code, i saw something already implemented, but not used.

Alternative: parsing the stderr. The problem is, i would have to redirect stderr into stdout and mingle programatically-readable text (json) with only-human-readable-text (language-specific/translatable error text). Handling this needs much more from everybody implementing steamctl in their codes, instead of handling this only in 1 place: in steamctl code.

Thank you!