Ask gpt for xpaths, not data

[rogeliotg]

This way, gpt gives xpaths for first page, and the library uses them to extract data from the other thousand pages, without cost

[jamesturk]

See #7 for a discussion of this, as you may be aware there's no reason to believe an XPath generated from a single page would work on others, the issue is robustness and will take a substantially different approach from the one here.