FEATURE: add JavaScript mode to ace (#27586)

This allows plugins to use Ace Editor in JavaScript mode. This will be used in Discourse AI when defining custom tools.

app/assets/javascripts/discourse/tests/integration/components/ace-editor-test.js

@@ -27,6 +27,11 @@ module("Integration | Component | ace-editor", function (hooks) {
     assert.ok(exists(".ace_editor"), "it renders the ace editor");
   });
 
+  test("javascript editor", async function (assert) {
+    await render(hbs`<AceEditor @mode="javascript" @content="test: true" />`);
+    assert.ok(exists(".ace_editor"), "it renders the ace editor");
+  });
+
   test("disabled editor", async function (assert) {
     await render(hbs`
       <AceEditor @mode="sql" @content="SELECT * FROM users" @disabled={{true}} />

lib/tasks/javascript.rake

@@ -250,9 +250,15 @@ task "javascript:update" => "clean_up" do
 
           ace_root = "#{library_src}/ace-builds/src-min-noconflict/"
 
-          addtl_files = %w[ext-searchbox mode-html mode-scss mode-sql mode-yaml worker-html].concat(
-            themes,
-          )
+          addtl_files = %w[
+            ext-searchbox
+            mode-html
+            mode-javascript
+            mode-scss
+            mode-sql
+            mode-yaml
+            worker-html
+          ].concat(themes)
 
           dest_path = dest.split("/")[0..-2].join("/")
           addtl_files.each { |file| FileUtils.cp_r("#{ace_root}#{file}.js", dest_path) }