feat: add pre_flight_authorization() builtin validation for conditional checks during Ash.can?

[emadshaaban92]

• Set pre_flight_authorization? in context earlier so it's available during validation, rather than setting it after subject construction.
• Use that private context to implement pre_flight_authorization()

Btw is there a reason context is ignored here?

%Ash.Changeset{} = changeset ->
    changeset
    |> Ash.Changeset.set_tenant(opts[:tenant] || changeset.tenant)
    |> Ash.Changeset.set_context(%{private: %{actor: actor}})

Also for %Ash.ActionInput{} and %Ash.Query{}

I know the caller can add whatever context they want in the subject itself when they call Ash.can like this:

Ash.can?(changeset |> Ash.Changeset.set_context(...), actor)

But the context is ignored if sent like this, which isn't what I expected since context almost always get merged in other places.

Ash.can?(changeset, actor, context: ...)

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Leave anything that you believe does not apply unchecked.

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• Update dependencies

[zachdaniel]

🚀 Thank you for your contribution! 🚀