feat: Support devDependencies install

[hairyf]

Clear and concise description of the problem

nip [packagename] -d / -D / ..

Suggested solution

Alternative

No response

Additional context

No response

Validations

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• Check that there isn't already an issue that request the same feature to avoid creating a duplicate.

[niansi-z]

You can try nip [packagename] -d

[oliver139]

You can try nip [packagename] -d

Nice, but as this tool is sticking to PNPM, I think it would be better if we can keep using -D instead

[niansi-z]

You can try nip [packagename] -d

Nice, but as this tool is sticking to PNPM, I think it would be better if we can keep using -D instead

feat: add support for uppercase 'D' flag in CLI options

I've submitted a PR, but I'm not sure if it will be accepted, as I don't know the original reason for ignoring the "D".