Use faker for structured few-shot

[zsimjee]

          Oh nice you added few shot prompting in there!  Could potentially change up the values with something like this: https://faker.readthedocs.io/en/master/.  If it's a true port of the js library then we can apply constraints to the values it produces based on the validators on the property.  Not necessary for the first pass through, but probably worth adding later.

Originally posted by @CalebCourier in https://github.com/guardrails-ai/guardrails/pull/517#discussion_r1428160281