feat: adds MAUI support

[tanderson-ld]

Requirements

• [x] I have added test coverage for new or changed functionality
• [x] I have followed the repository's pull request submission guidelines
• [x] I have validated my changes against all supported platform versions

Related issues

https://app.shortcut.com/launchdarkly/story/222947/dotnet-maui-support

Describe the solution you've provided

Removes portions of Xamarin code and replaces with MAUI API functionality. Replaces Xamarin test applications with single MAUI test application. Initial support for CI via Github Actions

[shortcut-integration[bot]]

This pull request has been linked to Shortcut Story #222947: Dotnet MAUI support.