feat: add dev config and graceful config handling

- Add deploy/dev/config.yaml for dev environment testing
- Mount config from ./config.yaml instead of project root
- Create template config if missing and exit gracefully
- Update .gitignore to only ignore root config.yaml

.gitignore

@@ -2,7 +2,7 @@ __pycache__/
 *.py[cod]
 .venv/
 .env
-config.yaml
+/config.yaml
 *.egg-info/
 dist/
 .pytest_cache/