feat: add frontend development guidelines and structure documentation

- Introduced API guidelines for interface contracts and request handling.
- Added design tokens usage guidelines for consistent styling across the project.
- Established DTO guidelines for defining request parameters and response data types.
- Created frontend structure guidelines to clarify directory organization and code placement rules.
- Compiled a comprehensive frontend development guideline document covering various aspects of the development process.
- Implemented quality guidelines to ensure code maintainability and adherence to best practices.

AI-RD-Workflow/50-cases/REQ-20260629-001-example/04-implementation/TASK-20260629-001.md

@@ -0,0 +1,34 @@
+---
+id: TASK-20260629-001
+case_id: REQ-20260629-001-example
+type: implementation-task
+stage: implementation
+owner_role: RD
+status: draft
+source_ids:
+  - DS-20260629-001
+derived_ids: []
+created: 2026-06-29
+updated: 2026-06-29
+---
+
+# TASK：创建目录和初始文档
+
+## 目标
+
+创建 AI 研发工作流研究区的第一版骨架。
+
+## 文件范围
+
+- `AI Coding/AI-RD-Workflow/`
+
+## 完成标准
+
+- 目录存在。
+- 核心规范和模板存在。
+- 示例 case 存在。
+- 追踪矩阵存在。
+
+## 验证方式
+
+使用 `find` 检查目录和文件结构。