style(UI): 调整加载遮罩层级和操作图标颜色

增加加载遮罩的z-index确保显示在最上层
为编辑和删除图标添加颜色提高视觉区分度

@@ -24,8 +24,8 @@
                     <div v-if="post.is_my" class="post-menu">
                         <slot name="menu">
                             <!-- Default menu items if needed, or left empty for parent to fill -->
-                            <van-icon name="edit" @click="emit('edit', post)" class="mr-2" />
-                            <van-icon name="delete-o" @click="emit('delete', post)" />
+                            <van-icon name="edit" @click="emit('edit', post)" class="mr-2" color="#4caf50" />
+                            <van-icon name="delete-o" @click="emit('delete', post)" color="#f44336" />
                         </slot>
                     </div>
                     <slot name="header-right" v-else></slot>

@@ -133,7 +133,7 @@
         </div>
 
         <!-- 上传加载遮罩 -->
-        <van-overlay :show="loading">
+        <van-overlay :show="loading" z-index="9999">
             <div class="loading-wrapper" @click.stop>
                 <van-loading vertical color="#FFFFFF">上传中...</van-loading>
             </div>