Closes#8836.
Atom constructors can be declared as private (project-private). project-private constructors can be called only from the same project. See the encapsulation.md docs for more info.
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Co-authored-by: Jaroslav Tulach <jaroslav.tulach@enso.org>
Co-authored-by: Radosław Waśko <radoslaw.wasko@enso.org>
Co-authored-by: Hubert Plociniczak <hubert.plociniczak@gmail.com>
Co-authored-by: Kaz Wesley <kaz@lambdaverse.org>
