[feature] Comments for steps

**Version and OS**
v0.48.5 on docker

**Is your feature request related to a problem? Please describe.**
I would love to attach comments to each step.

**Describe the solution you'd like**
An optional textbox just above the three buttons in each step. Even expandable, so it doesn't take too much step. Happy for it to be limited in length so as to not blow up the db.

**Describe the use-case and give concrete real-world examples**
To provide more context, help me remember the why behind the step or record possible gotchas. Think DNS records' comments on Cloudflare.

**Additional context**

Thanks!

Start by tracing how steps are rendered and stored in the Docker deployment. Add an optional, expandable comment field above each step's three buttons, with a bounded length and persistence in the database; done means comments can be entered, saved, displayed, and omitted without affecting existing steps.

Written by the indexing model from the issue text.