Make modern http streaming apis easily consumable in WebAssembly

[lewing]

The discussion in the pull request #111680 revolves around enabling response streaming for WebAssembly, which introduces a breaking change by disallowing synchronous reads and throwing NotSupportedExceptions instead. The main points discussed include:

All supported browsers support response streaming.
To disable response streaming and allow synchronous reads, a new runtime feature flag WebAssemblyEnableStreamingResponse can be set to false.
Here are the options for handling this change:

• Take the breaking change: Accept the breaking change and update the documentation to reflect that synchronous reads are no longer supported.
• Add a runtime feature flag: Implement the WebAssemblyEnableStreamingResponse feature flag, allowing users to opt-out of response streaming if necessary.
• Set the feature flag directly on requests that require it: Modify the code to set the WebAssemblyEnableStreamingResponse feature flag directly on specific requests that need synchronous reads.

You can view the full discussion and details of the pull request here.

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