[iOS][non-icu] HybridGlobalization implement missing functionalities

[mkhamoyan]

Investigate and implement below functionalities

• CompareInfo.GetSortKey
• CompareInfo.GetSortKeyLength
• CompareInfo.GetHashCode

Review and update the doc https://github.com/dotnet/runtime/blob/main/docs/design/features/globalization-hybrid-mode.md

Contributes to #80689

Tagging subscribers to this area: @dotnet/area-system-globalization
See info in area-owners.md if you want to be subscribed.

Issue Details

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Investigate and implement below functionalities

• CompareInfo.GetSortKey
• CompareInfo.GetSortKeyLength
• CompareInfo.GetHashCode

Review and update the doc https://github.com/dotnet/runtime/blob/main/docs/design/features/globalization-hybrid-mode.md

Contributes to #80689

Author:	mkhamoyan
Assignees:	mkhamoyan
Labels:	area-System.Globalization
Milestone:	-

Tagging subscribers to 'os-ios': @steveisok, @akoeplinger, @kotlarmilos
See info in area-owners.md if you want to be subscribed.

Issue Details

---

Investigate and implement below functionalities

• CompareInfo.GetSortKey
• CompareInfo.GetSortKeyLength
• CompareInfo.GetHashCode

Review and update the doc https://github.com/dotnet/runtime/blob/main/docs/design/features/globalization-hybrid-mode.md

Contributes to #80689

Author:	mkhamoyan
Assignees:	mkhamoyan
Labels:	area-System.Globalization, os-ios
Milestone:	-

[mkhamoyan]

Implemented by #95260