inspector: introduce inspector/promises API

PR-URL: #44250
Reviewed-By: Moshe Atlow <[email protected]>
Reviewed-By: Benjamin Gruenbaum <[email protected]>
Reviewed-By: Ruy Adorno <[email protected]>
Reviewed-By: Matteo Collina <[email protected]>
Reviewed-By: James M Snell <[email protected]>
Reviewed-By: Antoine du Hamel <[email protected]>

Author: ErickWendel