Unit Tests / test (push) Successful in 9s
## Summary - Closes #20 — name the AI assistant **Hesychia** in system / generation prompts - Add shared `assistant_identity.py` with `ASSISTANT_NAME` + concise calm/stillness tone - Prepend identity to chat (`llm_service`), RAG, data analysis, and the views system message - Document that identity lives in code (not env); add unit coverage ## Test plan - [x] `uv run python manage.py test chat_backend.tests.test_assistant_identity chat_backend.tests.test_services_llm chat_backend.tests.test_services_data_analysis` - [ ] Fresh chat: ask "who are you?" → responds as Hesychia - [ ] Confirm classifiers/moderators/title generator unchanged (not assistant identity) Related: companion frontend rebrand `chat_web_app#29`Reviewed-on: #22