docs: add note about object/array default values in defineModel

src/api/sfc-script-setup.md

@@ -314,6 +314,7 @@ const myRef = ref()
 </template>
 ```
 
+Also note that, as when using `withDefaults` with `defineProps`, default values for mutable reference types (like arrays or objects) should be wrapped in functions in `defineModel` to avoid accidental modification and external side effects.
 :::
 
 ### Modifiers and Transformers {#modifiers-and-transformers}

src/guide/components/v-model.md

@@ -115,6 +115,7 @@ const myRef = ref()
 </template>
 ```
 
+Also note that, as when using `withDefaults` with `defineProps`, default values for mutable reference types (like arrays or objects) should be wrapped in functions in `defineModel` to avoid accidental modification and external side effects.
 :::
 
 </div>