feat: 搭建应用基础框架

包含应用入口、根组件、路由配置（含登录守卫）、主布局、全局样式、ECharts 插件、类型定义、常量映射表及静态资源。

frontend/src/layouts/MainLayout.vue

@@ -0,0 +1,116 @@
+<script setup lang="ts">
+import { onMounted, onUnmounted } from 'vue'
+import { useRoute } from 'vue-router'
+import AppSidebar from '@/components/AppSidebar.vue'
+import AppHeader from '@/components/AppHeader.vue'
+import { useSystemStore } from '@/stores/system'
+import { useModelsStore } from '@/stores/models'
+
+const systemStore = useSystemStore()
+const modelsStore = useModelsStore()
+const route = useRoute()
+
+onMounted(() => {
+  // 启动顶部栏系统监控轮询
+  systemStore.start()
+  // 预加载模型列表缓存（列表页渲染模型名用）
+  modelsStore.load()
+})
+
+onUnmounted(() => {
+  systemStore.stop()
+})
+</script>
+
+<template>
+  <div class="main-layout">
+    <AppSidebar />
+    <div class="layout-main">
+      <AppHeader />
+      <main class="layout-content">
+        <div
+          class="page-canvas"
+          :class="{ 'is-self-surface': route.meta.pageSurface === 'self' }"
+        >
+          <router-view v-slot="{ Component }">
+            <component :is="Component" />
+          </router-view>
+        </div>
+      </main>
+    </div>
+  </div>
+</template>
+
+<style scoped lang="scss">
+.main-layout {
+  display: flex;
+  height: 100vh;
+  overflow: hidden;
+}
+
+.layout-main {
+  flex: 1;
+  display: flex;
+  flex-direction: column;
+  min-width: 0;
+  height: 100vh;
+}
+
+.layout-content {
+  flex: 1;
+  overflow-y: auto;
+  padding: 8px 8px 16px;
+  background-color: var(--app-shell-bg);
+  display: flex;
+  flex-direction: column;
+  min-height: 0;
+
+  &:has(.data-table-page),
+  &:has(.eval-page),
+  &:has(.manage-card-container) {
+    overflow-y: hidden;
+  }
+
+  &:has(.create-wizard-layout) {
+    overflow-y: hidden;
+
+    .page-canvas {
+      flex: 1 1 auto;
+      min-height: 0;
+    }
+  }
+}
+
+.page-canvas {
+  flex: 1 0 auto;
+  display: flex;
+  flex-direction: column;
+  width: 100%;
+  min-width: 0;
+  padding: 24px;
+  border-radius: 16px;
+  background-color: var(--app-page-bg);
+  box-shadow: var(--card-shadow);
+}
+
+.page-canvas.is-self-surface {
+  padding: 0;
+  border-radius: 0;
+  background-color: transparent;
+  box-shadow: none;
+}
+
+.page-canvas:has(.has-fixed-footer) {
+  margin-bottom: 56px;
+}
+
+/* 路由直接输出 PageCard，或显式声明根卡片宿主时，复用外层白色画布 */
+.page-canvas:not(.is-self-surface) > :deep(.page-card),
+.page-canvas:not(.is-self-surface) > :deep(.page-card-host > .page-card) {
+  margin-bottom: 0;
+  background-color: transparent;
+  border-radius: 0 !important;
+  box-shadow: none !important;
+}
+
+</style>