Replace Ace Editor with ToastUi editor in the ExecutionEnvironments form

Drop unused code related to the Ace markdown editor.

app/assets/javascripts/execution_environments.js

@@ -1,7 +0,0 @@
-$(document).on('turbolinks:load', function() {
-  if ($.isController('execution_environments')) {
-    if ($('.edit_execution_environment, .new_execution_environment').isPresent()) {
-      new MarkdownEditor('#execution_environment_help');
-    }
-  }
-});

app/assets/javascripts/markdown_ace_editor.js

@@ -1,14 +0,0 @@
-(function() {
-    window.MarkdownEditor = function(selector) {
-        var editor = ace.edit($(selector).next()[0]);
-        editor.on('change', function() {
-            $(selector).val(editor.getValue());
-        });
-        editor.setShowPrintMargin(false);
-        editor.setTheme(CodeOceanEditor.THEME);
-        var session = editor.getSession();
-        session.setMode('ace/mode/markdown');
-        session.setUseWrapMode(true);
-        session.setValue($(selector).val());
-    };
-})();

app/assets/stylesheets/base.css.scss

@@ -125,10 +125,6 @@ html[data-bs-theme="light"] {
   }
 }
 
-.markdown {
-  height: 200px;
-}
-
 .spinner {
   width: 40px;
   height: 40px;

app/views/execution_environments/_form.html.slim

@@ -1,4 +1,11 @@
-= form_for(@execution_environment) do |f|
+- content_for :head do
+  // Force a full page reload, see https://github.com/turbolinks/turbolinks/issues/326.
+     Otherwise, code might not be highlighted correctly (race condition)
+  meta name='turbolinks-visit-control' content='reload'
+  - append_javascript_pack_tag('toast-ui')
+  - append_stylesheet_pack_tag('toast-ui')
+
+= form_for(@execution_environment, builder: MarkdownFormBuilder) do |f|
   = render('shared/form_errors', object: @execution_environment)
   .mb-3
     = f.label(:name, class: 'form-label')
@@ -51,6 +58,5 @@
     = f.select(:testing_framework, @testing_framework_adapters, {include_blank: true}, class: 'form-control')
   .mb-3
     = f.label(:help, class: 'form-label')
-    = f.hidden_field(:help)
+    = f.markdown :help
-    .form-control.markdown
   .actions = render('shared/submit_button', f:, object: @execution_environment)