fix: conflicts and strip-dashed

[jly36963]

Addresses: #1952

Problem

When strip-dashed is true, the kebab case arguments are removed from argv.
When looking for conflicts, the result is a false negative. The conflicts are in kebab case while the argv arguments are in camel case, so the conflicts logic will never match the conflicting arguments.

Solution

When strip dashed is true, compare camelCase versions of conflicting against argv, to address the disparity between argv (camel) and conflicting (kebab).

Notes

This is important; please read

I didn't want to add any extra dependencies, so I made a very lightweight implementation of camelCase.
I borrowed heavily from lodash's source code. Let me know if I need to add proper credit, change the solution to avoid copying someone else's code, add unit tests, etc.

[bcoe]

I think you should have access to camelCase already through the yargs-parser dependency:

https://github.com/yargs/yargs-parser/blob/main/lib/string-utils.ts#L7

I believe I already use one or two methods off of it elsewhere.