Make it possible to customize historical banner's contents

[befeleme]

I'd like to be able to link to more documents on packaging.python.org that contain the bits of specification provided by PEP 639.
Currently the banner doesn't reflect that and confuses users as to where to look for the applicable information.

[encukou]

The wording in the PyPA template can be improved for this case, but you should be able to put more links in even now. See the sources of PEPs 652 & 697 for examples.

[skirpichev]

I suspect this belongs rather to the pep repo, isn't?

[befeleme]

Thank you, that is generally sufficient for my use case, although wording will not be as smooth with multiple entries.

[AA-Turner]

@befeleme what links do you want to add? If you have a draft of what you want the sticky box to look like/read, we can see how best to make it work.

[CAM-Gerlach]

You should be able to make the text completely custom if you want using the generic pep-banner directive. It accepts arbitrary RST and has no pre-filled text. Wasn't sure whether there would be an actual use case when I designed it, but glad to see there might be.