feat(typing): add type hints to hooks

[copalco]

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[vytas7]

Looks good, we just need to decide how the users should consume typing.py. Maybe it would be nice if it is importable without TYPE_CHECKING too? Should we document any aliases?

[CaselIT]

Since we dropped 3.7 we can probably avoid having everything inside a type check block. Will do

[CaselIT]

Maybe it would be nice if it is importable without TYPE_CHECKING too? Should we document any aliases?

For the moment I mentioned in the v4 chance log that any type alias should be treated as private, since it can change between releases.

I think once we are adding typing we can do a bit of cleanup and maybe provide a public set to aliaes

[vytas7]

LGTM now 👍
Thanks for the effort @copalco & @CaselIT!