Add and document reencrypt_fields command

README.md

@@ -91,3 +91,20 @@ See `.forgejo/workflows/build-deploy-staging.yaml` for the actual workflow.
 Deployment files are in the `deployment/kustomize` folder and makes use of [Kustomize](https://kustomize.io/) to account for differences between the deployment stages.
 Stages are configured with overlays in `deployment/kustomize/overlays/$environment`.
 
+## Maintenance and management commands
+
+You can interface with the Django server and project by running commands like this:
+
+```bash
+uv run --env-file=.env src/manage.py COMMAND
+```
+
+Useful commands:
+
+- ``migrate``: Make sure database migrations are applied.
+- ``showmigrations``: Show current database migrations status. Good for debugging.
+- ``runserver``: Run development server
+- ``clearsessions``: Clear away expired user sessions. Recommended to run regularly, e.g. weekly or monthly (doesn’t
+  need to be frequent, but otherwise, the database is going to bloat eventually)
+- ``reencrypt_fields``: Run after you changed your ``SERVALA_SECRET_KEY`` or ``SERVALA_SALT_KEY`` in order to use the
+  new keys, and be able to retire the previous ones.