Revert "Rewrite cosmetics and theme preferences (#1292)"

This reverts commit 8704d3acb3.

apps/frontend/src/composables/vue.ts

@@ -1,14 +0,0 @@
-/**
- * Creates a computed reference that uses a provide getter function called with an argument representing the current mount state of the component.
- * @param getter A getter function that will run with `mounted` argument representing whether or not the component is mounted.
- * @returns A computed reference that changes when component becomes mounted or unmounted.
- */
-export function useMountedValue<T>(getter: (isMounted: boolean) => T) {
-  const mounted = ref(getCurrentInstance()?.isMounted ?? false);
-
-  onMounted(() => (mounted.value = true));
-
-  onUnmounted(() => (mounted.value = false));
-
-  return computed(() => getter(mounted.value));
-}