UUID v7 support

[dantownsend]

Hi, maybe it’s time to start adding the new uuidv7() feature added in pgsql18!

Yes, now would be a good time - Python 3.14's uuid library also has uuid7 support too. We can tackle it in a separate PR, but definitely worth exploring.

Originally posted by @dantownsend in #1264

[dantownsend]

Related to #1279 and #1264