feat: 统一后端分页查询与前端服务层适配

后端新增通用分页模块，为报销单、员工、预算、agent 资产等
端点统一接入分页参数和游标查询，优化 repository 层分页实
现，前端服务层适配分页响应结构，完善预算图表和全局样式，
优化侧边栏和企业选择器组件，引入 Element Plus 插件注册。

web/package.json

@@ -14,14 +14,12 @@
     "@element-plus/icons-vue": "^2.3.2",
     "@vitejs/plugin-vue": "^5.2.4",
     "@vueuse/motion": "^3.0.3",
-    "chart.js": "^4.5.1",
     "echarts": "^6.1.0",
     "element-plus": "^2.14.0",
     "markdown-it": "^14.1.1",
     "pg": "^8.13.1",
     "vite": "^5.4.19",
     "vue": "^3.5.13",
-    "vue-chartjs": "^5.3.3",
     "vue-router": "^4.5.1"
   }
 }