refactor(manager): 优化全局空状态、错误图片占位并升级遗留消息语法

- 增加表格与树组件全局空状态 (el-empty) 样式规范
- 补齐视图图片语义化 alt，并添加全局图片加载异常 SVG 占位兜底
- 将砍价/秒杀/自定义面板中的 $Message 兼容语法替换为 ElMessage
- 清理冗余依赖 vuex，将 sass-loader 调整至 devDependencies

manager/package.json

@@ -26,7 +26,6 @@
     "nprogress": "^0.2.0",
     "pinia": "^4.0.3",
     "sass": "^1.63.6",
-    "sass-loader": "^10.4.1",
     "sockjs-client": "^1.4.0",
     "swiper": "^6.3.5",
     "uuid": "^8.3.2",
@@ -40,13 +39,13 @@
   "devDependencies": {
     "@vue/cli-plugin-babel": "^5.0.9",
     "@vue/cli-plugin-router": "^5.0.9",
-    "@vue/cli-plugin-vuex": "^5.0.9",
     "@vue/cli-service": "^5.0.9",
     "@vue/compiler-sfc": "^3.5.35",
     "compression-webpack-plugin": "^10.0.0",
     "css-loader": "^6.10.0",
     "less": "^4.2.0",
     "less-loader": "^11.1.4",
+    "sass-loader": "^10.4.1",
     "style-loader": "^3.3.4",
     "style-resources-loader": "^1.5.0",
     "vue-cli-plugin-style-resources-loader": "^0.1.5",