chore: pydantic-settings config, logging, CI workflow

Config (src/config.py):
- pydantic-settings Settings class: OLLAMA_URL, OLLAMA_MODEL, DEBUG
- Reads from .env (gitignored) with sane defaults
- settings singleton imported by health.py and agent.py

Removes two hardcodes:
- health.py: OLLAMA_URL="http://localhost:11434" → settings.ollama_url
- agent.py:  Ollama(id="llama3.2")              → settings.ollama_model

app.py:
- logging.basicConfig at INFO — requests/errors now visible in terminal
- docs_url/redoc_url gated on settings.debug (off by default)

pyproject.toml:
- pydantic-settings>=2.0.0 added to main dependencies
- hatch wheel config updated to include src/config.py

.env.example: documents all three env vars with inline comments
.gitignore: add !.env.example negation so the template gets committed

.github/workflows/tests.yml: runs pytest --cov on every push/PR
(ubuntu-latest, Python 3.11, pip cache)

All 27 tests pass.

https://claude.ai/code/session_01M4L3R98N5fgXFZRvV8X9b6

.gitignore

@@ -13,9 +13,10 @@ dist/
 venv/
 env/
 
-# Secrets / local config
+# Secrets / local config — commit only .env.example (the template)
 .env
 .env.*
+!.env.example
 
 # SQLite memory — never commit agent memory
 *.db