feat(ops): #18 use commitizen (#21)

* feat: use commitizen (#19)

* feat(commitizen): #18 add commitizen to dependencies

* doc(README): #18 describe publish process

* feat(commitizen): changelog path

* doc(commitizen): #18 update instruction

* chore(poetry): #18 🔒

* chore(doc): #18 -b

README.md

@@ -1,3 +1,16 @@
 # hamilflow
 
 Dataset of simple physical systems.
+
+## Publish process
+
+- Squash merge all features to `main`
+  - Use `feat(section): xxx`, `fix(section): yyy`, `chore(poetry): lock` etc as the squashed commit messages
+- Run `cz bump --dry` to determine the new version `X.Y.Z`. Or check out the [documentation](https://commitizen-tools.github.io/commitizen/bump/) for imposing a version
+- Run `git checkout -b release/X.Y.Z`
+- Run `cz bump`. This will
+  - Write `docs/changelog.md` from the commit messages; update the version in `pyproject.toml`
+  - Commit `docs/changelog.md` and `pyproject.toml`
+  - Create a new tag
+- Push to `release/X.Y.Z`
+- Merge to `main`, no need to squash, maybe don't delete the branch under release