More work towards support moving/deleting instance

docs/user_guide.md

@@ -235,6 +235,42 @@ All the data generated by the server is located in the `data/` directory:
 
 Restoring is as easy as adding your backed up `data/` directory into a fresh deployment.
 
+## Moving from another instance
+
+If you want to move followers from your existing account, ensure it is supported in your software documentation.
+
+For [Mastodon you can look at Moving or leaving accounts](https://docs.joinmastodon.org/user/moving/).
+
+First you need to grab the "ActivityPub actor URL" for your existing account:
+
+### Python edition
+
+```bash
+# For a Python install
+poetry run inv webfinger username@domain.tld
+```
+
+Edit the config.
+
+### Docker edition
+
+```bash
+# For a Docker install
+make account=username@domain.tld webfinger
+```
+
+Edit the config.
+
+#### Edit the config
+
+And add a reference to your old/existing account in `profile.toml`:
+
+```toml
+also_known_as = "my@old-account.com"
+```
+
+Restart the server, and you should be able to complete the move from your existing account.
+
 ## Tasks
 
 ### Pruning old data
@@ -280,3 +316,48 @@ make prune-old-data
 docker compose up -d
 rm data/microblogpub.db.bak
 ```
+
+### Moving to another instance
+
+**This section is just a draft.**
+
+If you want to migrate to another instance, you have the ability to move your existing followers to your new account.
+
+Your new account should reference the existing one, refer to your software configuration (for example [Moving or leaving accounts from the Mastodon doc](https://docs.joinmastodon.org/user/moving/)).
+
+Execute the Move task:
+
+#### Python edition
+
+```bash
+# For a Python install
+poetry run inv move username@domain.tld
+```
+
+#### Docker edition
+
+```bash
+# For a Docker install
+make account=username@domain.tld move
+```
+
+### Deleting the instance
+
+**This section is just a draft.**
+
+You want to delete your instance, you can request other instances to delete your remote profile.
+Once deleted, you won't be able to use your instance anymore.
+
+#### Python edition
+
+```bash
+# For a Python install
+poetry run inv self-destruct
+```
+
+#### Docker edition
+
+```bash
+# For a Docker install
+make self-destruct
+```