Port to Vue3 and TypeScript

Signed-off-by: Knut Ahlers <knut@ahlers.me>

src/components/clipboard-button.vue

@@ -8,10 +8,13 @@
     <i :class="{'fas fa-fw fa-clipboard': !copyToClipboardSuccess, 'fas fa-fw fa-circle-check': copyToClipboardSuccess}" />
   </button>
 </template>
-<script>
-export default {
+
+<script lang="ts">
+import { defineComponent } from 'vue'
+
+export default defineComponent({
   computed: {
-    hasClipboard() {
+    hasClipboard(): boolean {
       return Boolean(navigator.clipboard && navigator.clipboard.writeText)
     },
   },
@@ -23,7 +26,7 @@ export default {
   },
 
   methods: {
-    copy() {
+    copy(): void {
       navigator.clipboard.writeText(this.content)
         .then(() => {
           this.copyToClipboardSuccess = true
@@ -43,5 +46,5 @@ export default {
       type: String,
     },
   },
-}
+})
 </script>