src: add ability to look up platform based on `Environment*`

This should eventually remove any necessity to use the global-state
`GetMainThreadMultiIsolatePlatform()`.

PR-URL: https://github.com/nodejs/node/pull/30467


Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Gireesh Punathil <gpunathi@in.ibm.com>