Port over System.Runtime.InteropServices docs for .NET 9

[jkoritzinsky]

Summary

Fixes dotnet/runtime#105986

[carlossanlop]

Left one comment for you to consider. There's also a problem with a type that cannot be found. Depending on the root cause, we may have to wait until P7 is released before merging this PR.

[learn-build-service-prod]

Learn Build status updates of commit 735b497:

✅ Validation status: passed

File	Status	Preview URL	Details
xml/System.Runtime.InteropServices.Marshalling/ComVariantMarshaller.xml	✅Succeeded	View
xml/System.Runtime.InteropServices.Marshalling/ReadOnlySpanMarshaller`2+ManagedToUnmanagedOut.xml	✅Succeeded	View
xml/System.Runtime.InteropServices.Swift/SwiftSelf`1.xml	✅Succeeded	View
xml/System.Runtime.InteropServices/CollectionsMarshal.xml	✅Succeeded	View

For more details, please refer to the build report.

For any questions, please:

• Try searching the learn.microsoft.com contributor guides
• Post your question in the Learn support channel

[learn-build-service-prod]

Learn Build status updates of commit 20123b7:

✅ Validation status: passed

File	Status	Preview URL	Details
xml/System.Runtime.InteropServices.Marshalling/ComVariantMarshaller.xml	✅Succeeded	View
xml/System.Runtime.InteropServices.Marshalling/ReadOnlySpanMarshaller`2+ManagedToUnmanagedOut.xml	✅Succeeded	View
xml/System.Runtime.InteropServices.Swift/SwiftSelf`1.xml	✅Succeeded	View
xml/System.Runtime.InteropServices/CollectionsMarshal.xml	✅Succeeded	View

For more details, please refer to the build report.

For any questions, please:

• Try searching the learn.microsoft.com contributor guides
• Post your question in the Learn support channel