refactor(@schematics/angular): deprecate testRunner option

DEPRECATED: The `testRunner` option in the `application`, `library`, and `ng-new` schematics is deprecated. New projects will only be configured with Vitest in a future version.

Author: alan-agius4

packages/schematics/angular/application/schema.json

@@ -93,7 +93,8 @@
       "description": "The unit testing runner to use.",
       "type": "string",
       "enum": ["vitest", "karma"],
-      "default": "vitest"
+      "default": "vitest",
+      "x-deprecated": "New projects will only be configured with Vitest in a future version."
     },
     "skipPackageJson": {
       "type": "boolean",

packages/schematics/angular/library/schema.json

@@ -58,7 +58,8 @@
       "description": "The unit testing runner to use.",
       "type": "string",
       "enum": ["vitest", "karma"],
-      "default": "vitest"
+      "default": "vitest",
+      "x-deprecated": "New projects will only be configured with Vitest in a future version."
     }
   },
   "required": ["name"]

packages/schematics/angular/ng-new/index.ts

@@ -51,7 +51,7 @@ export default function (options: NgNewOptions): Rule {
     routing: options.routing,
     style: options.style,
     skipTests: options.skipTests,
-    testRunner: options.testRunner,
+    testRunner: options.testRunner === TestRunner.Karma ? TestRunner.Karma : undefined,
     skipPackageJson: false,
     // always 'skipInstall' here, so that we do it after the move
     skipInstall: true,

packages/schematics/angular/ng-new/schema.json

@@ -112,7 +112,8 @@
       "description": "The unit testing runner to use.",
       "type": "string",
       "enum": ["vitest", "karma"],
-      "default": "vitest"
+      "default": "vitest",
+      "x-deprecated": "New projects will only be configured with Vitest in a future version."
     },
     "createApplication": {
       "description": "Create a new initial application project in the new workspace. When false, creates an empty workspace with no initial application. You can then use the `ng generate application` command to create applications in the `projects` directory.",