📝 docs(mini-program-ui): 移除Unsplash占位图详细使用示例和代码

- 删除Unsplash占位图的格式说明、使用示例和关键词分类
- 移除相关TypeScript实现代码示例
- 精简为仅保留基础占位图使用原则

.roo/rules/16-mini-program-ui.md

@@ -41,54 +41,6 @@
 #### Unsplash 占位图使用
 - **默认占位图**：使用 Unsplash 提供的免费高质量图片
 - **图片尺寸**：根据组件需求选择合适的尺寸
-- **格式**：`https://source.unsplash.com/{width}x{height}/?{关键词}`
-
-#### 使用示例
-- **头像占位图**：`https://source.unsplash.com/200x200/?portrait`
-- **封面占位图**：`https://source.unsplash.com/400x300/?nature`
-- **背景占位图**：`https://source.unsplash.com/800x600/?landscape`
-- **商品图片**：`https://source.unsplash.com/300x300/?product`
-
-#### 关键词分类
-- **人物**：portrait, person, people, man, woman
-- **自然**：nature, landscape, mountain, forest, ocean
-- **城市**：city, building, architecture, street
-- **抽象**：abstract, pattern, texture, gradient
-- **技术**：technology, computer, phone, digital
-- **食物**：food, coffee, fruit, restaurant
-- **商业**：business, office, workspace, meeting
-
-#### 实现代码示例
-```typescript
-// 头像组件
-const AvatarPlaceholder = ({ size = 200 }) => {
-  const placeholderUrl = `https://source.unsplash.com/${size}x${size}/?portrait`;
-  return <Image src={placeholderUrl} mode="aspectFill" />;
-};
-
-// 封面组件
-const CoverPlaceholder = ({ width = 400, height = 300, keyword = 'nature' }) => {
-  const placeholderUrl = `https://source.unsplash.com/${width}x${height}/?${keyword}`;
-  return <Image src={placeholderUrl} mode="aspectFill" />;
-};
-
-// 带错误处理的占位图
-const SmartImage = ({ src, placeholder, ...props }) => {
-  const [imageSrc, setImageSrc] = useState(src || placeholder);
-  
-  const handleError = () => {
-    setImageSrc(placeholder);
-  };
-  
-  return (
-    <Image 
-      src={imageSrc} 
-      onError={handleError}
-      {...props}
-    />
-  );
-};
-```
 
 ### 2.3 字体规范