feat: add live playground for interactive schema demonstration

[Copilot]

Implements a split-view playground to demonstrate Object UI's schema-driven rendering without requiring backend infrastructure.

Implementation

New Application: apps/playground/

• Split-view interface: example selector | JSON editor | live preview
• 7 curated examples across primitives, layouts, and forms
• Real-time JSON validation with error display
• Responsive viewport toggles (desktop/tablet/mobile)
• One-click schema export

Workspace Integration

• Added apps/* to monorepo configuration
• New scripts: playground:dev, playground:build, playground:preview

Technical Decisions

• Textarea editor instead of Monaco (avoids CDN dependencies in restricted environments)
• Direct SchemaRenderer integration demonstrating standalone usage
• Tailwind-native examples showing className customization

Examples Structure

// apps/playground/src/data/examples.ts
export const examples = {
  'button-variants': `{
    "type": "button",
    "label": "Purple Custom Button",
    "className": "bg-purple-500 hover:bg-purple-700 text-white"
  }`,
  'dashboard': `{ /* KPI cards + responsive grid */ }`,
  // ... 5 more examples
};

export const exampleCategories = {
  'Primitives': ['simple-page', 'input-states', 'button-variants'],
  'Layouts': ['grid-layout', 'dashboard', 'tabs-demo'],
  'Forms': ['form-demo']
};

Screenshots

Dashboard Example

Button Variants with Custom Tailwind Styling

Responsive Preview Modes

Usage

pnpm playground:dev    # http://localhost:5174
pnpm playground:build

Original prompt

---

This section details on the original issue you should resolve

<issue_title>构建一个 Live Playground (实时演练场) (用于展示引擎能力)</issue_title>
<issue_description>对于 Object UI 这样一个“元数据驱动”的渲染引擎，Examples（示例/演示） 的设计至关重要。

普通的组件库（如 AntD）只需要展示“代码 vs 组件”。
但你需要展示的是 “JSON Schema vs 界面”。

** 构建一个 Live Playground (实时演练场) (用于展示引擎能力)。

我们重点讨论如何构建这个 Live Playground，因为这是你项目的“门面”。

---

1. 架构位置

建议在 Monorepo 中创建一个独立的 Vite 应用：

packages/
apps/
└── playground/        # 👈 对外发布的演示站点
    ├── package.json
    ├── src/
    │   ├── data/      # 预置的 JSON 案例
    │   ├── layout/    # 演练场的布局框架
    │   └── App.tsx
    └── vite.config.ts

---

2. 核心交互设计：Split View (左右分屏)

这是低代码引擎的标准演示形态。

• 左侧 (Editor): Monaco Editor (VS Code 风格编辑器)，显示 JSON/YAML。
• 右侧 (Preview): <SchemaRenderer /> 渲染结果。
• 功能：
• 实时编译： 左侧修改 JSON，右侧毫秒级更新。
• 错误高亮： 如果 JSON 格式错了，或者 Schema 校验不通过，直接标红。

---

3. 内容规划：你应该展示哪些 Case？

不要只放几个按钮，要按场景分类，证明你的引擎是“全能”的。

A. 基础原子 (Primitives)

展示你对 Shadcn 的封装能力。

• input.json: 各种状态的输入框（Required, Disabled, Error）。
• button.json: 不同 Level (Primary, Ghost, Destructive) 的按钮。

B. 复杂布局 (Layouts) - 这是你的杀手锏

证明你能搞定 B 端复杂的排版。

• grid-layout.json: 嵌套的 Grid，响应式 (col-span-1 md:col-span-2)。
• dashboard.json: 上面是 KPI 卡片，下面是图表和表格。
• tabs.json: 选项卡切换。

C. 数据联动 (Interactivity)

证明你不是静态的，支持数据域 (DataScope)。

• form-linkage.json:

• 当“国家”选择“中国”时，“省份”下拉框才显示。

• 表达式：visibleOn: "${country === 'cn'}"。

• crud-table.json: 一个带搜索栏、分页、操作列的完整表格。

---

4. 代码实现参考 (The Playground App)

你需要安装 @monaco-editor/react 来实现代码编辑体验。

// apps/playground/src/App.tsx
import React, { useState, useEffect } from 'react';
import Editor from '@monaco-editor/react';
import { SchemaRenderer } from '@object-ui/react';
import { standardComponents } from '@object-ui/components';
import { examples } from './data'; // 预置的案例列表

export default function Playground() {
  const [selectedExample, setSelectedExample] = useState('dashboard');
  const [code, setCode] = useState(examples['dashboard']);
  const [schema, setSchema] = useState(null);

  // 实时解析 JSON
  useEffect(() => {
    try {
      const parsed = JSON.parse(code);
      setSchema(parsed);
    } catch (e) {
      // JSON 语法错误时保持上一次的渲染，或显示错误提示
    }
  }, [code]);

  return (
    <div className="flex h-screen w-screen">
      {/* 1. 侧边栏：选择案例 */}
      <aside className="w-64 bg-slate-50 border-r p-4">
        <h1 className="font-bold mb-4">Object UI Examples</h1>
        {Object.keys(examples).map(key => (
          <button 
            key={key}
            onClick={() => { setSelectedExample(key); setCode(examples[key]); }}
            className={`block w-full text-left px-2 py-1 rounded ${key === selectedExample ? 'bg-blue-100 text-blue-600' : ''}`}
          >
            {key}
          </button>
        ))}
      </aside>

      {/* 2. 左侧：代码编辑器 */}
      <div className="w-1/2 h-full border-r">
        <Editor 
          height="100%" 
          defaultLanguage="json" 
          value={code} 
          onChange={(val) => setCode(val || '')}
          options={{ minimap: { enabled: false }, fontSize: 14 }}
        />
      </div>

      {/* 3. 右侧：实时预览 */}
      <div className="w-1/2 h-full bg-white overflow-auto p-8">
        <div className="max-w-4xl mx-auto border rounded-lg shadow-sm p-6 bg-white">
          {schema ? (
            <SchemaRenderer 
              schema={schema} 
              components={standardComponents} 
              // 模拟数据源，证明是 Standalone 的
              dataSource={{ find: async () => [] }} 
            />
          ) : (
             <div className="text-red-500">Invalid JSON</div>
          )}
        </div>
      </div>
    </div>
  );
}

---

5. 关键卖点植入

在 Playground 里，你还需要通过一些小细节来强化你的产品定位：

1. Tailwind Class 编辑:

• 在演示 button.json 时，故意加一行 "className": "bg-purple-500 hover:bg-purple-700"。
• 让用户修改这个字符串，右边按钮颜色立马变。
• 目的： 展示 "Tailwind Native" 的威力。

2. 移动端预览模式:

• 在右侧预览区加一个 [手机/平板/桌面] 的切换按钮，调整容器宽度。
• 目的： 展示 Responsive Grid 的能力。

3. Schema 导出:

• 加一个 "Copy Schema" 按钮。
• 目的： 方便开发者直接把调好的配置复制到他们的项目中。

总结

你的 apps/playground 是最好的销售工具。
它不需要后端，不需要 ObjectOS。它只需要证明：“给我一段 JSON，我还你一个漂亮的界面。”</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes 构建一个 **Live Playground (实时演练场)** (用于展示引擎能力) #7

---

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[Copilot]

Pull request overview

This PR introduces a Live Playground application for Object UI - a standalone interactive demo environment that showcases the schema-driven rendering engine's capabilities through real-time JSON editing and live preview.

Changes:

• Created a new Vite-based playground application in apps/playground with split-view interface (example gallery, JSON editor, and live preview)
• Added 7 curated example schemas organized into three categories: Primitives, Layouts, and Forms
• Implemented responsive viewport toggles and one-click schema copy functionality
• Updated workspace configuration to include the new apps/* directory

Reviewed changes

Copilot reviewed 15 out of 17 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
pnpm-workspace.yaml	Added apps/* to workspace packages
package.json	Added playground development, build, and preview scripts
apps/playground/vite.config.ts	Configured Vite with path aliases to monorepo packages
apps/playground/tsconfig.json	TypeScript configuration for the playground app
apps/playground/tailwind.config.js	Tailwind CSS configuration matching Shadcn design system
apps/playground/src/main.tsx	React application entry point
apps/playground/src/index.css	Tailwind base styles and CSS variables for theming
apps/playground/src/data/examples.ts	Seven example schemas demonstrating various UI capabilities
apps/playground/src/App.tsx	Main playground component with split-view layout
apps/playground/postcss.config.js	PostCSS configuration for Tailwind processing
apps/playground/package.json	Playground dependencies and scripts
apps/playground/index.html	HTML entry point for the playground
apps/playground/README.md	Documentation for the playground application
apps/playground/.gitignore	Standard Node.js project ignore patterns
README.md	Removed trailing empty lines

Files not reviewed (1)

• pnpm-lock.yaml: Language not supported

[Copilot]

The schema state uses any type which bypasses TypeScript's type checking. Consider using a more specific type from @object-ui/types or define an interface for the schema structure to maintain type safety.

[Copilot]

This file defines example schemas as template strings but lacks JSDoc annotations for the individual examples and exported types. According to CodingGuidelineID 1000000, properties in the Schema should have JSDoc documentation to enable auto-generated documentation for the open-source community. Add JSDoc comments for the examples object, ExampleKey type, and exampleCategories to document their purpose and structure.

[Copilot]

The inline string transformation logic for converting kebab-case to Title Case is complex and duplicates formatting logic. Extract this into a utility function (e.g., formatExampleName) to improve readability and maintainability.

[github-actions]

✅ All checks passed!

• ✅ Type check passed
• ✅ Tests passed
• ✅ Lint check completed

[github-actions]

✅ All checks passed!

• ✅ Type check passed
• ✅ Tests passed
• ✅ Lint check completed