Add responsive panels to the single-column layout (#10820)

* Add responsive panels to the single-column layout

* Fixes

* Fix not being able to save the preference

* Fix code style issues

* Set max-height on the compose textarea and add a link to relationship manager

app/javascript/mastodon/components/autosuggest_input.js

@@ -49,7 +49,7 @@ export default class AutosuggestInput extends ImmutablePureComponent {
     autoFocus: PropTypes.bool,
     className: PropTypes.string,
     id: PropTypes.string,
-    searchTokens: ImmutablePropTypes.list,
+    searchTokens: PropTypes.arrayOf(PropTypes.string),
     maxLength: PropTypes.number,
   };