Introduce UIA movement/expansion by page

[carlos-zamora]

Summary of the Pull Request

This adds support for the "Page" text unit in UiaTextRange. In terminals, the viewport will be used as the size of a "page". This should feel natural since "page up" and "page down" have been supported for quite some time. By extension, "expanding" to the page should return the same as getting the visible range.

This includes more UIA Table Tests that were manually verified and constructed from direct testing with Microsoft Word.

PR Checklist

• Closes UIA: support movement by page #13756
• Tests added/passed

Detailed Description of the Pull Request / Additional comments

(Coming soon)

Validation Steps Performed

(Coming soon)

[carlos-zamora]

What's left for me to do:

• update the UIA Table tests with behavior verified from Microsoft Word
• implement "movement" (in progress)

This will be done by Windows Terminal v1.18. Ideally, I could even get this in for v1.17, but I suspect between the time it takes to review this and the last minute work that keeps popping up, I think it's a safer bet to say this'll be in 1.18 for sure.

CC @codeofdusk

[carlos-zamora]

Getting closer. Tests are written. Just need to resolve the last 13 failing tests. They all have to do with non-degenerate ranges (which, unfortunately, is a pretty bug number of scenarios).

@codeofdusk feel free to get a copy of the current implementation. I'll probably be able to finish fixing this up on Monday though. Again, keep in mind, non-degenerate ranges are the ones that are returning unexpected results. So be wary of that if you're testing it out.

[alex19EP]

Hello, @carlos-zamora whats the status on this?