ui: monaco: upgrade to 0.57, drop monaco-editor-webpack-plugin

- Migrate entry points to the 0.57 exports scheme (monaco-editor/editor,
  languages/features/typescript/register)
- Wire workers via the official MonacoEnvironment.getWorker +
  new Worker(new URL(...)) integration; webpack emits them as shared-chunk
  classic workers (chrome 70 compatible), total assets -21%
- Keep css/html/json language features (register.all) and route their
  worker labels; json is used by the cmeditor textareas
- Replace removed esm/vs/nls.messages with an inline implementation in the
  nls shim
- Drop MinChunkSizePlugin: it merged worker chunks into the main chunk and
  broke the runtime id module (webpack#15416)
- Remove monaco-editor-webpack-plugin dependency
- loadMonaco() now returns the loaded feature module exports, e.g.
  loadMonaco(['typescript']).typescript.javascriptDefaults

packages/ui-default/components/monaco/loader.ts

@@ -32,7 +32,11 @@ const loaders = {
     if (resource) setLocaleData(resource);
   },
   markdown: () => import('./languages/markdown'),
-  typescript: () => import('./languages/typescript').then((m) => m.loadTypes()),
+  typescript: async () => {
+    const m = await import('./languages/typescript');
+    await m.loadTypes();
+    return m;
+  },
   yaml: () => import('./languages/yaml'),
   external: async (monaco, feat) => {
     for (const item of await getFeatures(`monaco-${feat}`)) {
@@ -49,7 +53,13 @@ const loaders = {
 
 let loadPromise = Promise.resolve();
 
-export async function load(features = ['markdown']) {
+export async function load(features = ['markdown']): Promise<{
+  monaco: typeof import('monaco-editor/editor');
+  registerAction: typeof import('./index').registerAction;
+  customOptions: typeof import('./index').customOptions;
+  renderMarkdown: typeof import('./index').renderMarkdown;
+  [feature: string]: any;
+}> {
   let s = Date.now();
   await loadPromise;
   let resolve;
@@ -59,6 +69,7 @@ export async function load(features = ['markdown']) {
     console.log('Loading monaco editor');
   }
   const res = await import('./index');
+  const featureExports: Record<string, any> = {};
   if (!loaded) {
     console.log('Loaded monaco editor in', Date.now() - s, 'ms');
     loaded = [];
@@ -75,7 +86,7 @@ export async function load(features = ['markdown']) {
     s = Date.now();
     console.log('Loading monaco feature:', feat);
     try {
-      if (loaders[feat]) await loaders[feat]();
+      if (loaders[feat]) featureExports[feat] = await loaders[feat]();
       else await loaders.external(res.default, feat);
       console.log('Loaded monaco feature:', feat, 'in', Date.now() - s, 'ms');
       loaded.push(feat);
@@ -90,6 +101,7 @@ export async function load(features = ['markdown']) {
     registerAction: res.registerAction,
     customOptions: res.customOptions,
     renderMarkdown: res.renderMarkdown,
+    ...featureExports,
   };
 }