[browser][MT] initialize runtime in a web worker - with JS interop directed to UI thread

[pavelsavara]

ST, but consistent experience with MT

Related #114918

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[MihuBot]

I'm a bot. Here is a possible related and/or duplicate issue (I may be wrong):

• [browser] initialize runtime in a web worker - with it's own messaging #114918

[JakeYallop]

What would happen here for projects where the runtime is already started in a web worker (I have a single-threaded WASM app that does this)?

[OptimusPi]

What does this mean? I do this today with bootsharp and AOTNative-LLVM 🤷‍♀️