Add exclusive lists (#22048)

Co-authored-by: Liam Cooke <liam@liamcooke.com>
Co-authored-by: John Holdun <john@johnholdun.com>
Co-authored-by: Effy Elden <effy@effy.space>
Co-authored-by: Lina Reyne <git@lina.pizza>
Co-authored-by: Lina <20880695+necropolina@users.noreply.github.com>
Co-authored-by: Claire <claire.github-309c@sitedethib.com>

app/javascript/mastodon/locales/en.json

@@ -356,6 +356,7 @@
   "lists.delete": "Delete list",
   "lists.edit": "Edit list",
   "lists.edit.submit": "Change title",
+  "lists.exclusive": "Hide these posts from home",
   "lists.new.create": "Add list",
   "lists.new.title_placeholder": "New list title",
   "lists.replies_policy.followed": "Any followed user",