Case insensitive user text input comparison

[akinsmosu]

fixes #1906

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Changes

Summary
This PR makes TextPrompt<string> case-insensitive when matching user input against defined choices. Previously, inputs such as "yes" would fail to match "Yes".

What this change does
When the TextPrompt's generic is a string and the user did not explicitly provide a comparer, it automatically configures _comparer to StringComparer.OrdinalIgnoreCase.

Adds a theory-based test to verify case-insensitive matching.

All existing behavior remains unchanged for non-string TextPrompt<T> usage.

Implementation Notes
Added a typeof(T) == typeof(string) check in TextPrompt<T> to detect string-based prompts. _comparer is set to StringComparison.OrdinalIgnoreCase only if the user does not supply a comparer.

[akinsmosu]

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[patriksvensson]

Great first PR, but there are some changes I would like to see before I merge this 👍

[akinsmosu]

Thanks for the feedback! All suggestions applied.

[patriksvensson]

Hi!

Thanks so much for taking the time to submit this PR.
I really appreciate the contribution!

Unfortunately, I haven’t had the capacity to review this in a timely manner, and since it was opened, the repository has changed significantly. Because of that, this PR is no longer in a state where it can be reviewed or merged as-is. This is not your fault, but mine, and I'm sorry about this.

I’m going to close it for now to help keep things tidy. That said, if you’re still interested in contributing, please feel free to open a new pull request that’s up to date with the current state of the repository, and I’ll be happy to take a look when I can. I'll promise I'll do better this time around.

Thanks again for your work and for your interest in the project!