docs: add release steps to PUBLISHING.md

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

Author: pyramation

PUBLISHING.md

@@ -1,3 +1,51 @@
 # Publishing to PyPI
 
-https://packaging.python.org/en/latest/tutorials/packaging-projects/
+Package: https://pypi.org/project/pgsql-test/
+Reference: https://packaging.python.org/en/latest/tutorials/packaging-projects/
+
+The build backend is `poetry-core` (see `pyproject.toml`), but you do not need
+Poetry installed to release. The standard `build` + `twine` tools work.
+
+## One-time setup
+
+```bash
+python3 -m pip install --upgrade build twine
+```
+
+Create a PyPI API token at https://pypi.org/manage/account/#api-tokens and put it
+in `~/.pypirc`:
+
+```ini
+[pypi]
+  username = __token__
+  password = pypi-...
+```
+
+## Release
+
+1. Bump `version` in `pyproject.toml` (PyPI will reject a re-upload of an existing version).
+2. Make sure CI is green on `main`.
+3. Build and check:
+
+   ```bash
+   rm -rf dist
+   python3 -m build
+   twine check dist/*
+   ```
+
+4. Upload:
+
+   ```bash
+   twine upload dist/*
+   ```
+
+5. Tag and push:
+
+   ```bash
+   git tag v$(python3 -c "import tomllib;print(tomllib.load(open('pyproject.toml','rb'))['tool']['poetry']['version'])")
+   git push --tags
+   ```
+
+To do a dry run against TestPyPI first, add a `[testpypi]` section to `~/.pypirc`
+with a token from https://test.pypi.org and run
+`twine upload --repository testpypi dist/*`.