Introduce sidebar nav components, settings nav

app/components/main_with_sidenav_component.rb

@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+class MainWithSidenavComponent < ViewComponent::Base
+  def initialize(sidenav_partial:)
+    @sidenav_partial = sidenav_partial
+  end
+end