chore: 改用 logo.png 并放大 Logo 显示尺寸

三端引用切换为 packages/shared/public/logo.png，显示高度加倍，移除占位 logo.svg 与根目录误放的 logo.png。

Co-authored-by: Cursor <cursoragent@cursor.com>

apps/admin/src/views/Login.vue

@@ -26,7 +26,7 @@ async function login() {
   <div style="min-height: 100vh; display: flex; align-items: center; justify-content: center">
     <el-card style="width: 400px">
       <div style="text-align: center; margin-bottom: 24px">
-        <img src="/logo.svg" alt="TheBet365" style="height: 32px; width: auto" />
+        <img src="/logo.png" alt="TheBet365" style="height: 64px; width: auto" />
         <h2 style="margin-top: 12px; font-size: 16px; font-weight: 500">平台后台登录</h2>
       </div>
       <el-form @submit.prevent="login">