Improvement: Switch from status messages to codes

[ManiMatter]

Currently, “*Arr” apps are only supported in English.

Ability to use codes instead on error messages removes this limitation

Dependent on https://github.com/Sonarr/Sonarr/issues/6960

If you want support for *arr in languages other than English, feel free to upvote the above Sonarr-issue (or help it with code contributions or supporting sonarr team in other ways)