Provide way to give example inputs and outputs to promptpex

[bzorn]

Often prompts contain examples and they can be helpful in understanding what kinds of inputs the prompt expects and what the outputs should look like. These can inform rules but should be used separately as a way to generate similar inputs.

[bzorn]

Elements of solution

• Match what people do to specify examples
• Leverage examples to learn about what inputs look like
• Leverage examples to learn about what outputs look like

[pelikhan]

https://github.com/Azure-Samples/azure-search-openai-demo/blob/main/app/backend/approaches/prompts/ask_answer_question_vision.prompty

[bzorn]

Resolved with ability to read and sample multi-shot from an existing file of tests.