feat(templates): add intelligent PR template selection system

- Created specialized PR templates for different change types:
  - Backend template for Go/API changes
  - Frontend template for UI/UX changes
  - Documentation template for docs updates
  - General template for mixed changes
- Simplified default template from 270 to 115 lines
- Added GitHub Action for automatic template suggestion based on file types
- Auto-labels PRs with appropriate categories (backend/frontend/documentation)
- Provides friendly suggestions when default template is used

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: tinkle-community <tinklefund@gmail.com>

.github/PULL_REQUEST_TEMPLATE/docs.md

@@ -0,0 +1,107 @@
+# Pull Request - Documentation | 文档 PR
+
+> **💡 提示 Tip:** 推荐 PR 标题格式 `docs(scope): description`
+> 例如: `docs(api): update trading endpoints` | `docs(readme): add setup guide`
+
+---
+
+## 📝 Description | 描述
+
+**English:**
+
+
+**中文：**
+
+
+---
+
+## 📚 Type of Documentation | 文档类型
+
+- [ ] 📖 README update | README 更新
+- [ ] 📋 API documentation | API 文档
+- [ ] 🎓 Tutorial/Guide | 教程/指南
+- [ ] 📝 Code comments | 代码注释
+- [ ] 🔧 Configuration docs | 配置文档
+- [ ] 🐛 Fix typo/error | 修复拼写/错误
+- [ ] 🌍 Translation | 翻译
+
+---
+
+## 🔗 Related Issues | 相关 Issue
+
+- Closes # | 关闭 #
+- Related to # | 相关 #
+
+---
+
+## 📋 Changes Made | 具体变更
+
+**English:**
+-
+-
+
+**中文：**
+-
+-
+
+---
+
+## 📸 Screenshots (if applicable) | 截图（如适用）
+
+<!-- For documentation with images, diagrams, or UI examples -->
+<!-- 用于包含图片、图表或 UI 示例的文档 -->
+
+
+---
+
+## 🌐 Internationalization | 国际化
+
+- [ ] English version complete | 英文版本完整
+- [ ] Chinese version complete | 中文版本完整
+- [ ] Both versions are consistent | 两个版本内容一致
+- [ ] N/A (only one language needed) | 不适用（只需要一种语言）
+
+---
+
+## ✅ Checklist | 检查清单
+
+### Content Quality | 内容质量
+- [ ] Information is accurate and up-to-date | 信息准确且最新
+- [ ] Language is clear and concise | 语言清晰简洁
+- [ ] No spelling or grammar errors | 无拼写或语法错误
+- [ ] Links are valid and working | 链接有效且可用
+- [ ] Code examples are tested and working | 代码示例已测试且可用
+- [ ] Formatting is consistent | 格式一致
+
+### Documentation Standards | 文档标准
+- [ ] Follows project documentation style | 遵循项目文档风格
+- [ ] Includes necessary examples | 包含必要的示例
+- [ ] Technical terms are explained | 技术术语已解释
+- [ ] Self-review completed | 已完成自查
+
+### Git
+- [ ] Commits follow conventional format | 提交遵循 Conventional Commits 格式
+- [ ] Rebased on latest `dev` branch | 已 rebase 到最新 `dev` 分支
+- [ ] No merge conflicts | 无合并冲突
+
+---
+
+## 📚 Additional Notes | 补充说明
+
+**English:**
+
+
+**中文：**
+
+
+---
+
+**By submitting this PR, I confirm | 提交此 PR，我确认：**
+
+- [ ] I have read the [Contributing Guidelines](../../CONTRIBUTING.md) | 已阅读贡献指南
+- [ ] I agree to the [Code of Conduct](../../CODE_OF_CONDUCT.md) | 同意行为准则
+- [ ] My contribution is licensed under AGPL-3.0 | 贡献遵循 AGPL-3.0 许可证
+
+---
+
+🌟 **Thank you for your contribution! | 感谢你的贡献！**