Deprecate amd bundles

#21009 added the optional feature to use ES modules instead of AMD bundles, this follows up by emitting a deprecation if you don't do that.

Author: ef4

broccoli/amd-compat-entrypoints/ember-template-compiler.js

@@ -18,7 +18,7 @@ d('@ember/-internals/utils/index', emberinternalsUtilsIndex);
 import * as emberCanaryFeaturesIndex from '@ember/canary-features/index';
 d('@ember/canary-features/index', emberCanaryFeaturesIndex);
 
-/* 
+/*
 
 The classic build included these modules but not their dependencies, so they
 never worked. Keeping this comment to document why the list of modules differs in
@@ -200,3 +200,7 @@ d('simple-html-tokenizer', simpleHtmlTokenizer);
 if (typeof module === 'object' && module.exports) {
   module.exports = emberTemplateCompilerIndex;
 }
+
+console.log(
+  '\n\n--------\n+ Your app is using the legacy ember-template-compiler.js AMD bundle. This will be removed in ember-source 7.0. See https://deprecations.emberjs.com/id/using-amd-bundles for more details.\n--------'
+);

broccoli/amd-compat-entrypoints/ember.debug.js

@@ -473,3 +473,9 @@ d('rsvp', rsvp);
 if (typeof module === 'object' && typeof module.require === 'function') {
   module.exports = emberIndex.default;
 }
+
+emberDebugIndex.deprecate(
+  'Your app loaded Ember via a legacy AMD bundle. Opt into loading it from the modern ES modules by setting the use-ember-modules optional feature.',
+  false,
+  emberinternalsDeprecationsIndex.DEPRECATIONS.DEPRECATE_AMD_BUNDLES.options
+);

package.json

@@ -405,4 +405,4 @@
     }
   },
   "packageManager": "[email protected]"
-}
+}

packages/@ember/-internals/deprecations/index.ts

@@ -112,6 +112,16 @@ export const DEPRECATIONS = {
     until: '7.0.0',
     url: 'https://deprecations.emberjs.com/id/importing-inject-from-ember-service',
   }),
+  DEPRECATE_AMD_BUNDLES: deprecation({
+    for: 'ember-source',
+    id: 'using-amd-bundles',
+    since: {
+      available: '6.10.0',
+      enabled: '6.10.0',
+    },
+    until: '7.0.0',
+    url: 'https://deprecations.emberjs.com/id/using-amd-bundles',
+  }),
 };
 
 export function deprecateUntil(message: string, deprecation: DeprecationObject) {