FR: astrometry.net Add server URL

So you can target astormetry queries at local instances on the astrometry.net server, please consider adding the server URL so it can be localhost:8004 or whatever.

Thanks!

The issue names no implementation file or test. Start by locating the Python astrometry.net query entry point and checking where its server endpoint is configured. Done means callers can target localhost:8004 or another local instance while the existing default continues to work, with relevant coverage updated if available.

Written by the indexing model from the issue text.