add additional tests for coverage,

[phlptp]

Add some additional tests to try to get test coverage back to 100%

refactor the positional parsing to reduce code duplication

[codecov]

Codecov Report

All modified lines are covered by tests ✅

Files	Coverage Δ
include/CLI/impl/App_inl.hpp	100.00% <100.00%> (+0.83%)	⬆️
include/CLI/impl/Config_inl.hpp	100.00% <100.00%> (+1.68%)	⬆️

... and 6 files with indirect coverage changes

📢 Thoughts on this report? Let us know!.

[phlptp]

@henryiii I am going to merge this in one day unless you object. (2023-10-7)
There are no API changes only some code refactoring, new tests, and a fix for an edge case on specifically formatted inline comments on flags. then I will try to tackle the coverage in some of the other files, but this fixes app_inl and config_inl to 100% coverage.

[henryiii]

I've already approved so you can merge any time (you don't have to have my approval unless it's potentially controversial or something). And these sorts of cleanups & added tests don't need much review, IMO.