GF-4 (#4) Finalized layout

app/components/ui/avatar/AvatarFallback.vue

@@ -0,0 +1,21 @@
+<script setup lang="ts">
+import type { AvatarFallbackProps } from "reka-ui";
+import type { HTMLAttributes } from "vue";
+import { reactiveOmit } from "@vueuse/core";
+import { AvatarFallback } from "reka-ui";
+import { cn } from "@/lib/utils";
+
+const props = defineProps<AvatarFallbackProps & { class?: HTMLAttributes["class"] }>();
+
+const delegatedProps = reactiveOmit(props, "class");
+</script>
+
+<template>
+  <AvatarFallback
+    data-slot="avatar-fallback"
+    v-bind="delegatedProps"
+    :class="cn('bg-muted flex size-full items-center justify-center rounded-full', props.class)"
+  >
+    <slot />
+  </AvatarFallback>
+</template>