Revert app.vue changes that broke header styling

- Removed app.vue file that was interfering with navbar scroll behavior
- Restored min-h-screen in default.vue layout
- Restored min-height in body CSS
- Kept the mobile footer fixes which are working correctly

The header now properly changes to white background when scrolling past hero.

apps/website/app.vue

@@ -1,22 +0,0 @@
-<template>
-  <div id="__nuxt-app" class="h-full">
-    <NuxtLayout>
-      <NuxtPage />
-    </NuxtLayout>
-  </div>
-</template>
-
-<style>
-#__nuxt-app {
-  height: 100%;
-  display: flex;
-  flex-direction: column;
-}
-
-/* Ensure Nuxt's root wrapper inherits height */
-#__nuxt {
-  height: 100%;
-  display: flex;
-  flex-direction: column;
-}
-</style>

apps/website/assets/css/main.css

@@ -19,8 +19,8 @@ html {
 body {
   overscroll-behavior-y: contain;
   -webkit-overflow-scrolling: touch;
-  height: 100%;
-  height: -webkit-fill-available;
+  min-height: 100vh;
+  min-height: -webkit-fill-available;
   /* Prevent double-tap zoom on mobile */
   touch-action: manipulation;
   /* Prevent horizontal scrolling */

apps/website/layouts/default.vue

@@ -1,5 +1,5 @@
 <template>
-  <div class="h-full flex flex-col">
+  <div class="min-h-screen flex flex-col">
     <AppNavbar />
     <main class="flex-grow">
       <slot />