src: improve ToV8Value() functions

- Cache the `isolate` value between calls
- Introduce an overload for dealing with integers/numbers
- Use the vectored `v8::Array::New` constructor + `MaybeStackBuffer`
  for faster array creation

PR-URL: https://github.com/nodejs/node/pull/25288


Reviewed-By: Gus Caplan <me@gus.host>
Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>