Remove RequiresPreviewFeatures from QuicTransportOptions properties

[Copilot]

Remove RequiresPreviewFeatures from QuicTransportOptions properties

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Remove preview feature requirements from QuicTransportOptions properties

Description

Removes [RequiresPreviewFeatures] attribute from four properties in QuicTransportOptions:

• MaxBidirectionalStreamCount
• MaxUnidirectionalStreamCount
• MaxReadBufferSize
• MaxWriteBufferSize

These properties are already in PublicAPI.Shipped.txt and are now stable for general use.

Also removes the now-unused using System.Runtime.Versioning; directive.

Original prompt

Remove RequiresPreviewFeatures from QuicTransportOptions properties.

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[JamesNK]

@halter73 @BrennanConroy These properties have been experimental since .NET 7. We're not doing any work here, and the properties seem stable. I think it's fine to remove the preview attribute.

[Copilot]

Pull Request Overview

This PR removes the [RequiresPreviewFeatures] attribute from four properties in QuicTransportOptions, marking them as stable API. These properties have already been shipped in the public API surface.

• Removes preview feature restrictions from QUIC transport stream and buffer configuration properties
• Removes the now-unused using System.Runtime.Versioning; directive

[halter73]

Do we have anything else HTTP/3 related that still has [RequiresPreviewFeatures] other than IWebTransportSession? Should we remove it for that too?