Story 4.6: Test ChatQnA Orchestrator Interface

As a developer, I want pytest tests for the ChatQnA orchestrator interface, So that the custom OPEA overlay orchestrator is validated without real services.

FRs: FR21 | Sprint: 22

Acceptance Criteria:

• tests/test_chatqna.py created
• Tests verify orchestrator accepts valid chat requests and returns responses
• Tests verify user profile enrichment logic with mocked user data
• Tests verify multilingual translation integration with mocked translation service
• Tests verify citation formatting in response output
• Tests verify error handling when downstream services fail
• Tests verify streaming response handling (SSE)
• All downstream services mocked via conftest fixtures

NFRs: NFR6, NFR7, NFR8, NFR23, NFR24