migrate to Vue3

src/views/Home.vue

@@ -20,16 +20,16 @@
       <button @click="toggle">
         <transition name="fade" mode="out-in">
           <img
-            key="play"
             v-if="timeState === 'stopped'"
+            key="play"
             src="@/assets/play.svg"
             alt="play"
             width="50px"
             height="50px"
           />
           <img
+            v-else
             key="pause"
-            v-if="timeState === 'started'"
             src="@/assets/pause.svg"
             alt="pause"
             width="50px"
@@ -66,7 +66,7 @@
 </template>
 
 <script lang="ts">
-import { defineComponent, onMounted } from '@vue/composition-api'
+import { defineComponent, onMounted } from 'vue'
 import { useTimer } from '@/hooks/useTimer'
 import DevSession from '@/components/DevSession.vue'
 import ZoneMusic from '@/components/ZoneMusic.vue'