feat(client): 初始化前端壳与鉴权守卫（P1-5）

- 技术栈：React 18 + TypeScript + Vite + Tailwind

- API 层：ApiError + 401 自动刷新 + single-flight 重试

- 鉴权：内存 Access Token + Cookie Refresh + 启动 bootstrap

- RBAC：权限映射 + RequireAuth/RequirePermission 路由守卫

- 布局：OA 工作台壳层 + 侧边栏 + 5 个占位页面

- 样式：复用 hyb-web 视觉 token（单向同步）

- 文档：新增 client README，补充 server 联调说明

client/tailwind.config.js

@@ -0,0 +1,39 @@
+/** @type {import('tailwindcss').Config} */
+export default {
+  content: ["./index.html", "./src/**/*.{js,ts,jsx,tsx}"],
+  darkMode: "class",
+  theme: {
+    extend: {
+      colors: {
+        primary: {
+          DEFAULT: "#00398a",
+          50: "#e6ecf4",
+          100: "#ccd9ea",
+          200: "#99b4d5",
+          300: "#668ebf",
+          400: "#3369aa",
+          500: "#00398a",
+          600: "#002e6e",
+          700: "#002253",
+          800: "#001737",
+          900: "#000b1c"
+        },
+        secondary: "#5e718d",
+        background: {
+          light: "#f5f7f8",
+          dark: "#0f1723"
+        },
+        border: "#e2e8f0"
+      },
+      fontFamily: {
+        sans: ["Public Sans", "sans-serif"],
+        display: ["Public Sans", "sans-serif"]
+      },
+      borderRadius: {
+        lg: "0.5rem",
+        xl: "0.75rem"
+      }
+    }
+  },
+  plugins: []
+};