[PTRun Unit Converter] Support for 'sq' prefixed units

[OldUser101]

Summary of the Pull Request

Adds support for square units prefixed with sq. For example, sqm for square metres, instead of m^2.

PR Checklist

• Closes: Powertoys Run Unit Converter Sqft and Sqm #37553
• 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: Added/updated
• New binaries: Added on the required places
  • JSON for signing for new binaries
  • WXS for installer for new binaries and localization folder
  • YML for CI pipeline for new test projects
  • YML for signed pipeline
• Documentation updated: If checked, please file a pull request on our docs repo and link it here: #xxx

Detailed Description of the Pull Request / Additional comments

Used simple substitution to swap sq prefixed units with their ^2 equivalent. For example, sqft is substituted with ft², which is supported by UnitsNet.

For example, converting square feet to square metres can be done as follows:

Rather than:

This is additional to ^2 suffixed units, which are still available.

Validation Steps Performed

Basic testing done for each unit.

[Copilot]

Pull Request Overview

This PR adds support for square units prefixed with "sq" by converting them into their equivalent "²" notation, enabling users to use units like "sqm" instead of "m^2".

• Introduces SquareHandler to handle conversion of "sq" prefixed units.
• Integrates the new handler in the Parse method for unit conversion queries.

Files not reviewed (1)

• .github/actions/spell-check/expect.txt: Language not supported

[yeelam-gordon]

Let's migrate to v2.

[moooyo]

Close this PR due to another better impl has been merged.
#37862

[moooyo]

I'm pleasure to help if anyone want to migrate it to v2.