chore(quality): 接入 ESLint 与 GitLab CI,开启严格未用检查,构建期设计令牌守卫

- eslint.config.mjs(flat config):react-hooks/react-refresh/tseslint;自定义 no-restricted-syntax
  规则禁止 className 手拼基元类名(error 级,JSXAttribute 选择器精确限定,探针双向验证)与硬编码色值
- tsconfig:noUnusedLocals/noUnusedParameters 置 true
- package.json 新增 typecheck/lint/test/verify:tokens 脚本;build 串联令牌校验(verify-tokens.sh
  防止 <alpha-value> 类静默失效回归);pnpm-lock.yaml 入库供 CI --frozen-lockfile
- .gitlab-ci.yml:lint/typecheck/test/build 四作业,MR 与默认分支触发,dist 产物留存一周

frontend/package.json

@@ -5,8 +5,12 @@
   "type": "module",
   "scripts": {
     "dev": "vite",
-    "build": "tsc && vite build",
-    "preview": "vite preview"
+    "build": "tsc && vite build && sh scripts/verify-tokens.sh",
+    "preview": "vite preview",
+    "typecheck": "tsc --noEmit",
+    "lint": "eslint \"src/**/*.{ts,tsx}\"",
+    "test": "node --experimental-strip-types --test \"src/**/*.test.ts\"",
+    "verify:tokens": "sh scripts/verify-tokens.sh"
   },
   "dependencies": {
     "react": "^18.3.1",
@@ -14,13 +18,19 @@
     "react-router-dom": "^6.30.6"
   },
   "devDependencies": {
+    "@eslint/js": "^10.0.1",
     "@types/react": "^18.3.3",
     "@types/react-dom": "^18.3.0",
     "@vitejs/plugin-react": "^4.3.1",
     "autoprefixer": "^10.4.19",
+    "eslint": "^9.39.5",
+    "eslint-plugin-react-hooks": "^7.1.1",
+    "eslint-plugin-react-refresh": "^0.5.7",
+    "globals": "^17.12.0",
     "postcss": "^8.4.39",
     "tailwindcss": "^3.4.6",
     "typescript": "^5.5.3",
+    "typescript-eslint": "^8.70.1",
     "vite": "^5.3.4"
   }
 }