proxyman set or unset does not behave predictably with option 1

When proxyman is run with either set or unset with the option to modify all targets the behavior becomes unpredictable, some times it will set/unset the variables in /ect/enviroment some times not. Behavior is unpredictable but tends more towards not setting variables

Reproduce proxyman set and unset with the all-targets option (option 1), checking /etc/environment after each run. Trace the command entry point handling these operations and identify why updates are inconsistent. Done means both commands reliably set or remove the expected variables for all targets.

Written by the indexing model from the issue text.