Add documentation for CompareOptions.NumericOrdering

[PranavSenthilnathan]

Add documentation for new API introduced in dotnet/runtime#109861

[dotnet-policy-service]

Tagging subscribers to this area: @dotnet/area-system-globalization

[Copilot]

Pull request overview

This PR adds documentation for the new CompareOptions.NumericOrdering API introduced in dotnet/runtime#109861. The changes update several XML documentation files to include references to the new option and clarify when it's valid or invalid for use.

• Adds the NumericOrdering member documentation to CompareOptions.xml
• Updates existing CompareOptions member summaries to use consistent phrasing ("A string comparison that..." instead of "Indicates that...")
• Adds NumericOrdering to parameter documentation lists across CompareInfo and GlobalizationExtensions methods
• Updates remarks sections to note that NumericOrdering is invalid for indexing methods (like IndexOf, IsPrefix, IsSuffix, LastIndexOf)

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 3 comments.

File	Description
xml/System.Globalization/CompareOptions.xml	Adds NumericOrdering member documentation; updates existing member summaries to use consistent style; improves remarks section with present tense
xml/System.Globalization/GlobalizationExtensions.xml	Adds NumericOrdering to the GetStringComparer options parameter documentation
xml/System.Globalization/CompareInfo.xml	Adds NumericOrdering to Compare, GetSortKey parameter documentation; updates remarks to note NumericOrdering is invalid for indexing methods