Get rid of TOX_USER_STATUS_BUSY + 1

[nicoonoclaste]

• This is an invalid value for that enum type.
• All that code will silently break when the enum datatype is changed.

Do we have similar instances of that “idiom” in the current codebase?

[pranomostro]

ag 'TOX_[0-9A-Z_]+ \+ 1' | grep -v LENGTH returns only one occasion where a enum member is incremented.

[nicoonoclaste]

@pranomostro Yes, and fixing it requires, as far as I can see, an API-breaking change.
I guess that's why @iphydf set the v0.2 milestone

[GrayHatter]

This is just a few lines of code to set a new default.

The question is, do we simply use STATUS_NORMAL?

Or do we want to try to handle the invalid case again?