docs: explain that visibility rules do not apply transitively

[AlexTereshenkov]

Clarify that visibility rules are only for direct dependencies.

We don't use any images in the documentation yet, it seems so I didn't want to add an image just for this. I think the explanation should be clear enough, but this is what I thought.

graph BT;
src.app.main-->src.library.public
src.app.main-->src.library.private.X
src.app.main-->src.library.private.Y

src.library.public-->src.library.private.X
src.library.public-->src.library.private.Y

linkStyle default stroke:green
linkStyle 1 stroke:red
linkStyle 2 stroke:red

[kaos]

Looks right to me. I wish another mind besides mine finds this legible before landing ;)

[kaos]

Does this suggest there is a missing feature here?
Not sure how easy/expensive it would be to support, though..

[AlexTereshenkov]

Thanks for taking a look, Andreas! I don't think this is a feature that needs a dedicated implementation. We have, in fact, this implemented by providing access to transitive dependencies. I think this is a fairly rare use case, so I think providing goals that could be piped is sufficient. :)

[huonw]

Looks fine, although your nifty diagram would definitely be a good addition (if we have an approach to adding images/diagrams) too 👍