feat: 添加项目 Logo 和优化主页

- 添加 favicon.png, logo.png, hero-bg.png 静态资源
- 优化 index.html 配置
- 优化 HomePage.vue 样式

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/components/GlobalSidebar.vue

@@ -7,11 +7,7 @@
       title="主页"
       @click="switchPage('home')"
     >
-      <svg width="32" height="32" viewBox="0 0 24 24" fill="none" xmlns="http://www.w3.org/2000/svg">
-        <path d="M12 2L2 7L12 12L22 7L12 2Z" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"/>
-        <path d="M2 17L12 22L22 17" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"/>
-        <path d="M2 12L12 17L22 12" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"/>
-      </svg>
+      <img src="/logo.png" alt="Home" class="sidebar-logo-img">
     </button>
 
     <!-- 导航项 -->
@@ -117,11 +113,14 @@ const switchPage = (page) => {
 
 .sidebar-logo.active {
   background: var(--info-bg);
+  box-shadow: 0 0 15px rgba(96, 165, 250, 0.2);
 }
 
-.sidebar-logo svg {
+.sidebar-logo-img {
   width: 100%;
   height: 100%;
+  object-fit: cover;
+  border-radius: inherit;
 }
 
 /* 导航区域 */