feat: add new option to allow waiting thread start before thread-spawn return

[toyobayashi]

https://github.com/WebAssembly/wasi-threads?tab=readme-ov-file#design-choice-pthreads

4. in pthread_create, call wasi_thread_spawn with the configured start_args and use atomic.wait to wait for the start_args->thread->tid value to change (note that for web polyfills this may not be necessary since creation of web workers is not synchronous)

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[toyobayashi]

I guess it also not available on StackBlitz.