Add dark mode, allow noise settings to be changed while running, add timer toggle

src/components/AppBar.vue

@@ -0,0 +1,16 @@
+<template>
+  <v-app-bar
+    app
+    color="secondary"
+    dark
+    dense
+  >
+    <v-container fill-height>
+      <v-switch
+        v-model="$vuetify.theme.dark"
+        inset
+        label="Dark Mode"
+      />
+    </v-container>
+  </v-app-bar>
+</template>