docs: fix reactivity API examples that do not match Vue 3.5 behavior

src/api/application.md

@@ -646,8 +646,8 @@ Configure a prefix for all IDs generated via [useId()](/api/composition-api-help
 
   ```js
   // in a component:
-  const id1 = useId() // 'myApp:0'
-  const id2 = useId() // 'myApp:1'
+  const id1 = useId() // 'myApp-0'
+  const id2 = useId() // 'myApp-1'
   ```
 
 ## app.config.throwUnhandledErrorInProduction <sup class="vt-badge" data-text="3.5+" /> {#app-config-throwunhandlederrorinproduction}

src/api/reactivity-core.md

@@ -306,7 +306,7 @@ Runs a function immediately while reactively tracking its dependencies and re-ru
 
   ```js
   watchEffect(async (onCleanup) => {
-    const { response, cancel } = doAsyncWork(newId)
+    const { response, cancel } = doAsyncWork(id.value)
     // `cancel` will be called if `id` changes, cancelling
     // the previous request if it hasn't completed yet
     onCleanup(cancel)
@@ -320,7 +320,7 @@ Runs a function immediately while reactively tracking its dependencies and re-ru
   import { onWatcherCleanup } from 'vue'
 
   watchEffect(async () => {
-    const { response, cancel } = doAsyncWork(newId)
+    const { response, cancel } = doAsyncWork(id.value)
     // `cancel` will be called if `id` changes, cancelling
     // the previous request if it hasn't completed yet
     onWatcherCleanup(cancel)
@@ -513,7 +513,7 @@ Watches one or more reactive data sources and invokes a callback function when t
   Pausing / resuming the watcher: <sup class="vt-badge" data-text="3.5+" />
 
   ```js
-  const { stop, pause, resume } = watch(() => {})
+  const { stop, pause, resume } = watch(source, callback)
 
   // temporarily pause the watcher
   pause()

src/api/reactivity-utilities.md

@@ -184,7 +184,7 @@ Converts a reactive object to a plain object where each property of the resultin
     [K in keyof T]: ToRef<T[K]>
   }
 
-  type ToRef = T extends Ref ? T : Ref<T>
+  type ToRef<T> = T extends Ref ? T : Ref<T>
   ```
 
 - **Example**

src/guide/extras/reactivity-in-depth.md

@@ -302,6 +302,10 @@ const plusOne = computed(() => count.value + 1, {
 // access plusOne, should trigger onTrack
 console.log(plusOne.value)
 
+// onTrigger is only called while plusOne has a subscriber,
+// such as a watcher or a component that renders it
+watchEffect(() => plusOne.value)
+
 // mutate count.value, should trigger onTrigger
 count.value++
 ```