docs: document the ui.movement.edit config option

This option was introduced in #4283, but was not documented apart from
`prev` and `next`'s help text on the --edit/--no-edit flags.

cli/src/config-schema.json

@@ -177,6 +177,16 @@
                     "type": "boolean",
                     "default": false,
                     "description": "Whether the built-in templates should show cryptographic signature information"
+                },
+                "movement": {
+                    "type": "object",
+                    "properties": {
+                        "edit": {
+                            "type": "boolean",
+                            "description": "Whether the next and prev commands should behave as if the --edit flag was passed",
+                            "default": false
+                        }
+                    }
                 }
             }
         },

docs/config.md

@@ -343,6 +343,22 @@ To prevent rewriting commits authored by other users:
 Ancestors of the configured set are also immutable. The root commit is always
 immutable even if the set is empty.
 
+### Behavior of prev and next commands
+
+If you prefer using an "edit-based" workflow, rather than squashing
+modifications into parent changes, you may find yourself using the `prev` and
+`next` commands with their `--edit` flag often to move between your changes. You
+can avoid having to type the `--edit` flag every time you need it by actually
+making it the default:
+
+```toml
+[ui.movement]
+edit = true
+```
+
+You can pass the `--no-edit` flag to `prev` and `next` if you find yourself
+needing the original behavior.
+
 ## Log
 
 ### Default revisions