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/00-intake/INTAKE-20260629-001.md

@@ -0,0 +1,33 @@
+---
+id: INTAKE-20260629-001
+case_id: REQ-20260629-001-example
+type: intake
+stage: user-requirement
+owner_role: PM
+status: draft
+source_ids: []
+derived_ids:
+  - UR-20260629-001
+created: 2026-06-29
+updated: 2026-06-29
+---
+
+# 原始输入：AI 研发工作流
+
+## 背景
+
+希望在当前 vault 中开始研究 AI 研发工作流，方向是 `spec + skill` 双驱动。
+
+## 原始描述
+
+每个需求由多个文档关联起来，从开始输入到后续逐项产出都能追踪。阶段包括用户需求、研发需求、详细设计、编码、测试。
+
+## 期望结果
+
+逐步完成相关 skill 和规范说明，支持长期迭代和调优。
+
+## 待确认问题
+
+- OR、DR、DS 的最终命名和字段是否需要贴合现有公司标准。
+- 每个阶段是否需要正式审批人和审批记录。
+- 是否需要自动化脚本检查追踪关系。