async_hooks: multi-tenant promise hook api

I've introduced a new promise_hook module which exposes the PromiseHook API in V8 more directly to userland. I've also updated async_hooks to consume this new API for its own promise lifecycle events. This is part of my ongoing effort to break down async_hooks into more purpose-specific components that can be used directly rather than using async_hooks itself which conflates many different data sources and can be awkward to use at times. Feedback is welcome. 😸