Add:Tasks widget in appbar for merging m4bs & remove old m4b merge routes

client/components/widgets/NotificationWidget.vue

@@ -0,0 +1,25 @@
+<template>
+  <div v-if="tasksRunning" class="w-4 h-4 mx-3 relative">
+    <div class="flex h-full items-center justify-center">
+      <widgets-loading-spinner />
+    </div>
+  </div>
+</template>
+
+<script>
+export default {
+  data() {
+    return {}
+  },
+  computed: {
+    tasks() {
+      return this.$store.state.tasks.tasks
+    },
+    tasksRunning() {
+      return this.tasks.some((t) => !t.isFinished)
+    }
+  },
+  methods: {},
+  mounted() {}
+}
+</script>