Change public accounts pages to mount the web UI (#19319)

* Change public accounts pages to mount the web UI

* Fix handling of remote usernames in routes

- When logged in, serve web app
- When logged out, redirect to permalink
- Fix `app-body` class not being set sometimes due to name conflict

* Fix missing `multiColumn` prop

* Fix failing test

* Use `discoverable` attribute to control indexing directives

* Fix `<ColumnLoading />` not using `multiColumn`

* Add `noindex` to accounts in REST API

* Change noindex directive to not be rendered by default before a route is mounted

* Add loading indicator for detailed status in web UI

* Fix missing indicator appearing while account is loading in web UI

app/views/statuses/_simple_status.html.haml

@@ -53,18 +53,18 @@
       = t 'statuses.show_thread'
 
   .status__action-bar
-    = link_to remote_interaction_path(status, type: :reply), class: 'status__action-bar-button icon-button icon-button--with-counter modal-button' do
+    %span.status__action-bar-button.icon-button.icon-button--with-counter
       - if status.in_reply_to_id.nil?
         = fa_icon 'reply fw'
       - else
         = fa_icon 'reply-all fw'
       %span.icon-button__counter= obscured_counter status.replies_count
-    = link_to remote_interaction_path(status, type: :reblog), class: 'status__action-bar-button icon-button modal-button' do
+    %span.status__action-bar-button.icon-button
       - if status.distributable?
         = fa_icon 'retweet fw'
       - elsif status.private_visibility? || status.limited_visibility?
         = fa_icon 'lock fw'
       - else
         = fa_icon 'at fw'
-    = link_to remote_interaction_path(status, type: :favourite), class: 'status__action-bar-button icon-button modal-button' do
+    %span.status__action-bar-button.icon-button
       = fa_icon 'star fw'