[PTRun][UnitConverter]Add support for sq prefix for square units

[PesBandi]

Summary of the Pull Request

Adds support for using sq instead of ^2, for example sqcm instead of cm^2.

PR Checklist

• Closes: Powertoys Run Unit Converter Sqft and Sqm #37553, [PTRun Unit Converter] Support for 'sq' prefixed units #37648
• Communication: I've discussed this with core contributors already. If work hasn't been agreed, this work might be rejected
• Tests: Added/updated and all pass
• Localization: All end user facing strings can be localized
• Dev docs: No need
• New binaries: None
• Documentation updated: Not yet

Detailed Description of the Pull Request / Additional comments

• Replaces sq with ² if before a unit that can be square.
• Works for the following units: s, μm, mm, cm, dm, m, km, mil, in, ft, yd, mi, nmi, ft (US)
• Unlike the original PR, this also works with more complex units, such as m/sqs instead of m/s^2.

Screenshots that weren't possible before:

Validation Steps Performed

Added tests, manually tested a bunch of units

[moooyo]

LGTM.

But, could you please add at least one picture in the description to show the usage of your new units format?

[moooyo]

/azp run

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[PesBandi]

Hi @moooyo, thanks for the review. I've added some screenshots to the description, you can check them out.

[PesBandi]

Do you think I should mention this in the docs?

[moooyo]

Do you think I should mention this in the docs?

I believe so. It's better.