fix(schema): document use case for typescript.shim (#26607)

packages/schema/src/config/typescript.ts

@@ -79,6 +79,9 @@ export default defineUntypedSchema({
      *
      * We recommend instead letting the [official Vue extension](https://marketplace.visualstudio.com/items?itemName=Vue.volar)
      * generate accurate types for your components.
+     *
+     * Note that if you may wish to set this to `true` if you are using other libraries, such as ESLint,
+     * that are unable to understand the type of `.vue` files.
      */
     shim: false
   }