constants: stop exporting UV_ constants

[bnoordhuis]

...and possibly other internal constants as well.

Context: #33246

Example: os.constants exports UV_UDP_REUSEADDR, which makes no sense for that module and isn't usable outside of core.

Introduced in dcccbfd which turned the mostly-internal, undocumented constants module into something that's public and documented but apparently without reviewing whether it makes sense to export/document everything.

[jasnell]

Heh, without reviewing whether it makes sense to export/document everything ... those are two different things. They were already being exported long before dcccbfd landed... They were documented because there was simply no context about what should or should not be there and no information about what was or was not being used. (for context, UV_UDP_REUSEADDR was first exposed undocumented in public API via require('constants') in 592be01)

That said, so long as we take these through a proper deprecation cycle I'm all for limiting the constants that are exported to only those that are necessary. (deprecation would have been necessary with or without the added documentation given how long the require('constants') module had been public).

Would be good to get a list of constants we think could be deprecated together, then decide if we want to deprecate those in one big batch or small numbers at a time.

[juanarbol]

I'm +1 with this:

Would be good to get a list of constants we think could be deprecated together, then decide if we want to deprecate those in one big batch or small numbers at a time.