Removed all govuk css (#2814)

* Removed all govuk css

* Updated reference files

* Removing govuk js

* Fixed casing for modules, removed unused page

* Got more reference images

* Updated template page

* Removed govuk padding util

* Updated hint to uswds hint

* More govuk cleanup

* Commiting backstopjs ref files

* Fixed all unit tests that broke due to brittleness around govuk styling

* Added new ref images

* Final removal of govuk

* Officially removed all govuk references

* Updated reference file

* Updated link to button

* UI modernization

* Cleanup

* removed govuk escaping tests since they are no longer needed

* Fix CodeQL security issue in escapeElementName function

- Escape backslashes first before other special characters
- Prevents potential double-escaping vulnerability
- Addresses CodeQL alert about improper string escaping

* Found more govuk removal. Fixed unit tests

* Add missing pipeline check to pre-commit

* updated test

* Updated e2e test

* More update to e2e test

* Fixed another e2e test

* Simple PR comments addressed

* More updates

* Updated backstop ref files

* Refactored folder selection for non-admins

* Updated redundant line

* Updated tests to include correct mocks

* Added more ref files

* Addressing carlos comments

* Addressing Carlo comments, cleanup of window initing

* More cleanup and addressing carlo comments

* Fixing a11 scan

* Fixed a few issues with javascript

* Fixed for pr

* Fixing e2e tests

* Tweaking e2e test

* Added more ref files and cleaned up urls.js

* Fixed bug with creating new template

* Removed brittle test - addressed code ql comment

* e2e race condition fix

* More e2e test fixes

* Updated e2e tests to not wait for text sent

* Updated test to not wait for button click response

* Made tear down more resilent if staging is down

* reverted e2e test to what was working before main merge

* Updated backstopRef images

* Updated gulp to include job-polling differently

app/assets/stylesheets/main-uswds.scss

@@ -1,42 +1,34 @@
+// USWDS-based main stylesheet
+// This replaces the legacy Frontend Toolkit dependencies
+
+@use "sass:math";
+@use "uswds-core" as *;
+
 // Path to assets for use with file-url()
 $path: '/static/images/';
 
-// Dependencies from GOV.UK Frontend Toolkit
-// https://github.com/alphagov/govuk_frontend_toolkit/
-@import 'conditionals';
-@import 'shims';
-@import 'measurements';
-@import 'css3';
-@import 'colours';
-@import 'typography';
-@import 'grid_layout';
-@import 'helpers';
+// ------------------------------------
+// USWDS Core imports and utilities
+// ------------------------------------
 
-// Dependencies from GOVU.UK Frontend Toolkit, rewritten for this application
-@import 'url-helpers';
+// Helper functions and mixins
+@mixin box-sizing($type: border-box) {
+  box-sizing: $type;
+}
+
+@mixin border-radius($radius: 3px) {
+  border-radius: $radius;
+}
+
+@mixin box-shadow($shadow) {
+  box-shadow: $shadow;
+}
 
-// Specific to this application, needs to go at the top of the cascade
 @import 'globals';
 
-// Dependencies from GOV.UK Elements
-// https://github.com/alphagov/govuk_elements
-@import 'elements/helpers';
-@import 'elements/reset';
-@import 'elements/details';
-@import 'elements/elements-typography';
-@import 'elements/forms';
-@import 'elements/forms/form-multiple-choice';
-@import 'elements/forms/form-validation';
-@import 'elements/lists';
-@import 'elements/panels';
-@import 'elements/tables';
-
-// Dependencies from GOV.UK Frontend, packaged to be specific to this application
-@import './govuk-frontend/all';
-
-// Specific to this application
 @import 'local/typography';
 @import 'grids';
+
 @import 'components/site-footer';
 @import 'components/placeholder';
 @import 'components/sms-message';
@@ -67,7 +59,6 @@ $path: '/static/images/';
 @import 'components/vendor/responsive-embed';
 @import 'components/preview-pane';
 @import 'components/task-list';
-@import 'components/loading-indicator';
 @import 'components/area-list';
 @import 'components/content-metadata';
 
@@ -81,5 +72,4 @@ $path: '/static/images/';
 @import 'views/get_started';
 @import 'views/history';
 
-// TODO: break this up
 @import 'app';