Replace hard coded account nav with layout header

During development the account nav markup was copied over from the
layout header component instead of using the component itself.
This was probably due to time constraints.

The component audits are complaining that we are including the assets
for layout_header, when we are not using the component.

This removes the hard coded account navigation partial and uses
layout_header instead. This is technically duplicating the header, so
this change is dependent on some changes in Slimmer which will
conditionally reveal this layout header only when the account nav should
be present.

app/views/root/_base.html.erb

@@ -26,13 +26,39 @@
       } %>
     </div>
   </form>
-
-  <% unless hide_account_navigation %>
-    <%= render partial: 'account_navigation' %>
-  <% end %>
 <% end %>
 
 <% content_for :after_header do %>
+  <% unless hide_account_navigation %>
+    <%= render "govuk_publishing_components/components/layout_header", {
+      remove_bottom_border: true,
+      navigation_items: [
+      {
+        text: "Account",
+        href: Plek.new.find("account-manager"),
+        data: {
+          module: "explicit-cross-domain-links",
+          link_for: "accounts-signed-in",
+        },
+      },
+      {
+        text: "Sign out",
+        href: Plek.new.website_root + "/transition-check/logout",
+        data: {
+          module: "explicit-cross-domain-links",
+          link_for: "accounts-signed-in",
+        },
+      },
+      {
+        text: "Sign in",
+        href: Plek.new.website_root + "/transition-check/login",
+        data: {
+          module: "explicit-cross-domain-links",
+          link_for: "accounts-signed-out",
+        },
+      }],
+    } %>
+  <% end %>
   <div id="user-satisfaction-survey-container"></div>
   <% if @emergency_banner %>
     <%= render "notifications/emergency_banner", banner: @emergency_banner %>