fix: 移除重复的"全部"按钮，只更新样式

- HTML中已有"全部"按钮，不需要重复添加
- renderSubcategoryFilters只渲染子类别按钮
- 同时更新"全部"按钮的选中/未选中样式
- 选中时蓝色背景白色文字，未选中时白色背景灰色文字

templates/admin.html

@@ -534,11 +534,31 @@
                 container.innerHTML = '';
                 return;
             }
+            
+            // 获取当前筛选值
+            let currentFilter = '';
+            if (categoryId === 'ai-models') currentFilter = modelSubcategoryFilter;
+            else if (categoryId === 'gpus') currentFilter = gpuSubcategoryFilter;
+            else if (categoryId === 'cpus') currentFilter = cpuSubcategoryFilter;
+            else if (categoryId === dynamicCategoryId) currentFilter = dynamicSubcategoryFilter;
+            
+            // 只渲染子类别按钮，不渲染"全部"按钮（HTML里已有）
             container.innerHTML = cat.subcategories.map(sub => `
-                <button onclick="${filterFunction}('${sub.id}')" class="px-3 py-1 rounded text-sm bg-white border text-gray-600 hover:bg-gray-100">
-                    <i class="${sub.icon} mr-1"></i>${sub.name}
+                <button onclick="${filterFunction}('${sub.id}')" class="px-3 py-1 rounded text-sm ${currentFilter === sub.id ? 'bg-indigo-600 text-white' : 'bg-white border text-gray-600 hover:bg-gray-100'}">
+                    <i class="${sub.icon || 'ri-folder-line'} mr-1"></i>${sub.name}
                 </button>
             `).join('');
+            
+            // 更新"全部"按钮的样式
+            const parent = container.parentElement;
+            if (parent) {
+                const allBtn = parent.querySelector('button:first-of-type');
+                if (allBtn && currentFilter === '') {
+                    allBtn.className = 'px-3 py-1 rounded text-sm bg-indigo-600 text-white';
+                } else if (allBtn) {
+                    allBtn.className = 'px-3 py-1 rounded text-sm bg-white border text-gray-600 hover:bg-gray-100';
+                }
+            }
         }
 
         const colorMap = {