[wasm] Follow-up work for #100802

[kg]

#100802 disabled AOT module probing for interpreted WASM builds, but we should also optimize the code for AOT builds, and if possible, completely prune the irrelevant code from the binary in both configurations. We get ifdefs telling us we're targeting WASM and whether or not we're AOT'd, so it should be possible to strip a lot of code that isn't relevant to the target, and make sure we never call dlopen, never do weird filesystem probing, etc.

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