Compile the PWA help and account settings through Herb

Rails main compiles HTML templates through Herb under the 8.2 framework
defaults, which Campfire loads. Herb rejects `case` and its first `when`
in a single ERB tag, so the three pwa/ partials failed to compile, and
`herb:check` rejects ERB output in attribute names, which the account
settings' switch used for `checked`. Give `case` its own tag and build
the switch with tag.input; both render the same under Erubi.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
(cherry picked from commit 244e77241b)

test/controllers/accounts_controller_test.rb

@@ -10,6 +10,16 @@ class AccountsControllerTest < ActionDispatch::IntegrationTest
     assert_response :ok
   end
 
+  test "edit shows whether room creation is restricted to administrators" do
+    get edit_account_url
+    assert_select "label.switch input.switch__input[type=checkbox]:not([checked])"
+
+    accounts(:signal).update!(settings: { restrict_room_creation_to_administrators: true })
+
+    get edit_account_url
+    assert_select "label.switch input.switch__input[type=checkbox][checked][data-action='change->form#submit']"
+  end
+
   test "edit groups administrators separately from members with a divider" do
     get edit_account_url