This AI sample lacks risk & safety evaluation implementation

[carlotta94c]

As per email sent on 13th Dec with same subject, please double-check that this AI sample implements evaluations. In particular, what we are looking for is:

• Evaluation file(s) (might be a Jupyter notebook, a unit test script, etc.) that evaluates the solution against quality metrics
• Evaluation file(s) (might be a Jupyter notebook, a unit test script, etc.) that evaluates the solution against at least 2 safety metrics
• A descriptive section in your readme explaining how evaluation is implemented into the sample.

[carlotta94c]

@pamelafox Adding this issue here so we can track progress on the evaluation stream. I know you mentioned that eval implementation is done in separate repo https://github.com/Azure-Samples/ai-rag-chat-evaluator; so the agreed plan here is to move it into this repo and add documentation.

[pamelafox]

Related PR: #2233