Supports chat_web_app#31: public settings + /user/create/ create company/user and return JWTs for Stripe Checkout. Document flag in env/secret templates.
## 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
Closes#15
## Summary
- Add nullable `tokens_in` / `tokens_out` `IntegerField`s to `PromptMetric` to record real prompt/completion token counts per turn.
- New `extract_token_usage()` helper parses provider usage payloads (LangChain `usage_metadata`, OpenAI-style `prompt_tokens`/`completion_tokens`, Ollama `prompt_eval_count`/`eval_count`). When a provider reports no usage, the fields stay **null** — counts are never estimated/fabricated.
- `create_prompt_metric` / `finish_prompt_metric` in both `consumers.py` and `consumers_graph.py` accept and persist optional `tokens_in` / `tokens_out` (added to `update_fields` only when present).
- Admin panel (this ticket's deliverable):
- `PromptMetricAdmin` lists `tokens_in` / `tokens_out` and adds `event` / `model_name` / `has_file` filters.
- `ConversationAdmin` shows summed `tokens_in` / `tokens_out` / `tokens_total` per conversation.
- Migration `0023_promptmetric_tokens_in_promptmetric_tokens_out` (existing rows remain valid — null).
## Note on live capture
The streaming chat path uses LangChain `StrOutputParser`, which yields plain string chunks with no usage metadata, so live turns currently persist `null` tokens (honest, per acceptance criteria — no fabricated counts). The plumbing + helper are in place so wiring real provider usage is a drop-in once the services expose it.
## Follow-ups
- #16 — Show token in/out in chat web app UI (FE + API exposure)
- #17 — Token-based billing, quotas, and enforcement
## Test plan
- [x] `uv run python manage.py test` — full suite green (266 tests, 6 skipped)
- [x] Model: token fields default null + persist when set
- [x] `extract_token_usage`: LangChain / OpenAI / Ollama key variants, attribute sources, bool/float handling, missing usage → (None, None)
- [x] Metric lifecycle: tokens persist when provided, stay null when absent (both consumers)
- [x] Admin: conversation token totals sum across metrics and ignore other conversationsReviewed-on: #18
Closes#5
## Summary
- Replaces the three scattered test modules (`chat_backend/tests.py`, `services/tests.py`, `services/prompt_classifier/tests.py`) with a `chat_backend/tests/` package: **242 deterministic tests plus 6 opt-in live-Ollama checks**, up from 10 tests (3 of which were skipped and 4 of which were never even discovered).
- The suite runs fully offline — no Ollama, Chroma, SMTP or network access. LangChain runnables are replaced by a small `FakeChain`, Chroma/embeddings are mocked, email uses Django's locmem backend, and blobs go through `DatabaseStorage`.
- New `llm_be/test_runner.py` (wired via `TEST_RUNNER`) sets `SKIP_RAG_INIT=1` and an MD5 password hasher, so the suite cannot accidentally reach a model server and finishes in ~5s on SQLite (~17s on Postgres) instead of ~30s.
## Coverage
| Area | File |
|------|------|
| `TimeInfoBase.save`, slugs, `get_duration`, `file_exists`, cascades | `test_models.py` |
| `DatabaseStorage` save/open/exists/size/listdir/delete/times | `test_storage.py` |
| JWT claim, prompt/user/feedback/document serializers | `test_serializers.py` |
| auth + token, invite, feedback, company users, set-password, TOS | `test_views_users.py` |
| conversation list/order/create/detail/soft-delete | `test_views_conversations.py` |
| all four analytics endpoints, including empty-month behaviour | `test_views_analytics.py` |
| workspace + document upload/list/detail, 404 and 400 paths | `test_views_documents.py` |
| prompt classifier rules/parsing, moderation fail-safe, title cleanup | `test_services_classifiers.py` |
| CSV/XLSX/DOCX/PDF analysis, plot generation, error payloads | `test_services_data_analysis.py` |
| loader selection, filename sanitising, ingest, temp-file cleanup, search filters | `test_services_rag.py` |
| history formatting and streaming | `test_services_llm.py` |
| document re-index on create/delete, `SKIP_RAG_INIT` guard | `test_signals.py` |
| consumer DB helpers, LangGraph nodes (moderation, classification, generation, search flags), websocket routes | `test_consumers.py` |
Live checks (non-deterministic, need a model server):
```bash
cd llm_be
RUN_LIVE_OLLAMA_TESTS=1 uv run python manage.py test chat_backend.tests.test_live_ollama
```
## Bugs the tests surfaced (fixed here)
1. **`ConversationDetailView.post` silently dropped every prompt.** `import datetime` shadowed `from datetime import datetime`, so `datetime.now()` raised `AttributeError` inside a bare `except` and the endpoint returned 200 without saving. Now uses `timezone.now()`.
2. **Prompt attachments never reached the LLM.** `get_conversation_file_async` (both consumers) did `sync_to_async(prompt.file.read)` — with `DatabaseStorage` the attribute access itself opens the blob, i.e. a DB query in async context, raising `SynchronousOnlyOperation` that was swallowed and returned `(None, None)`. The read now happens inside the thread.
3. **`DatabaseStorage._save` crashed on a str-backed `ContentFile`** (`TypeError: sequence item 0: expected a bytes-like object`); chunks are encoded when needed.
4. **`services/prompt_classifier/__init__.,py`** (note the comma) meant the directory was only an implicit namespace package, which is why its test module was never collected. Renamed, and its duplicate live-Ollama tests folded into `test_live_ollama.py`.
Known-broken paths deliberately left untested and unchanged: `reset_password` / `ResetUserPassword` reference an unimported `requests` plus undefined locals, and `DocumentDetailView.get` references an undefined `workspaces` on its success path. Worth a follow-up ticket.
## Test plan
- [x] `cd llm_be && uv run python manage.py test` → 248 tests, OK (6 skipped, all opt-in live)
- [x] Same suite against Postgres 16 (`DATABASE_URL=postgres://…`) → OK, matching the containerized run in `deploy.yml`
- [x] `uv run black` clean on all added files
- [ ] Gitea Actions **Unit Tests** + **CI** green on this PRReviewed-on: #12
westfarn