[Enhancement]: NeMo Guardrails example integration

[willkill07]

Affected area

Middleware or guardrails, Plugins

Problem or opportunity

NeMo integration should highlight interop with existing NeMo products.

Add a NeMo Guardrails plugin example for Python.

Proposed enhancement

Add a NeMo Guardrails plugin example for Python.

Runtime contract and binding impact

N/A

Alternatives considered

N/A

Acceptance criteria

End-to-end example showing sample integration with nemoguardrails