feat(layout): 添加视频壁纸组件并优化布局结构

- 引入 VideoWallpaper 组件作为全局视频背景- 调整主内容区域层级和定位方式
- 更新窗口尺寸配置为 1280x720
- 优化 Header 组件层级防止被遮挡
- 移除页面级视频壁纸实现逻辑

src/routes/+page.svelte

@@ -1,14 +1,12 @@
-<script lang="ts">
-	import video from '$lib/assets/video/c9df6498_517c_4fee_a39d_72b43f3425fd.mp4';
-</script>
-
-<div class="app-wallpaper" >
-	<video class="absolute  h-screen object-cover -z-10" autoplay muted loop playsinline>
-		<source src="{video}" type="video/mp4">
-	</video>
-</div>
-
-<style lang="scss">
-
-
-</style>
+<div class="relative pt-10 px-4 ">
+	<h1>123</h1>
+	haisdjiasjd
+	as
+	dasdasd
+	as
+	d
+	asd
+	asd
+	as
+	d
+</div>