refactor(wel): 重构欢迎页为模块化组件

- 将欢迎页整体结构拆分为多个功能区组件，提高代码可维护性
- 移除原有欢迎横幅、指标卡、图表区、下方区及快捷入口的静态实现
- 引入并注册 SectionKpi、SectionStructure、SectionBusiness 等八个子组件
- 删除冗余样式，更新整体背景和布局样式
- 精简模板内容，仅保留子组件渲染及页脚版权信息
- 移除无用的响应式数据、计算属性及方法
- 包含依赖包 echarts 的新增，支持后续图表功能开发

src/views/wel/components/section-kpi.vue

@@ -0,0 +1,183 @@
+<template>
+  <section class="wel-sec">
+    <div class="wel-sec__head">
+      <span class="wel-sec__title">核心经营指标</span>
+      <wel-filters />
+    </div>
+
+    <el-row :gutter="16">
+      <el-col v-for="card in cards" :key="card.label" :xs="24" :md="8">
+        <div class="kpi-card">
+          <div class="kpi-card__top">
+            <span class="kpi-card__label">{{ card.label }}</span>
+            <span
+              class="kpi-card__badge"
+              :class="card.trend >= 0 ? 'is-up' : 'is-down'"
+            >
+              环比 {{ card.trend >= 0 ? '+' : '' }}{{ card.trend }}%
+            </span>
+          </div>
+          <div class="kpi-card__value">
+            {{ card.value }}<span class="kpi-card__unit">{{ card.unit }}</span>
+          </div>
+          <ul class="kpi-card__subs">
+            <li v-for="s in card.subs" :key="s.name">
+              <span class="kpi-card__sub-name">{{ s.name }}</span>
+              <span class="kpi-card__sub-value">{{ s.value }}</span>
+              <span
+                v-if="typeof s.change === 'number'"
+                class="kpi-card__sub-change"
+                :class="s.change >= 0 ? 'is-up' : 'is-down'"
+              >
+                {{ s.change >= 0 ? '↑' : '↓' }} {{ Math.abs(s.change) }}%
+              </span>
+            </li>
+          </ul>
+        </div>
+      </el-col>
+    </el-row>
+  </section>
+</template>
+
+<script>
+import WelFilters from './wel-filters.vue';
+
+export default {
+  name: 'section-kpi',
+  components: { WelFilters },
+  data() {
+    return {
+      // Mock：营业额/运单量/利润等核心指标，对接统计接口后替换
+      cards: [
+        {
+          label: '营业额',
+          value: '58,814.0',
+          unit: '万元',
+          trend: 12.6,
+          subs: [
+            { name: '毛利率', value: '23.5%', change: 1.2 },
+            { name: '运输成本', value: '45,031 万元', change: -0.8 },
+            { name: '回款金额', value: '39,640 万元', change: 3.4 },
+            { name: '应收账款', value: '19,174 万元', change: -2.1 },
+          ],
+        },
+        {
+          label: '运单量',
+          value: '1,497.1',
+          unit: '单',
+          trend: 8.4,
+          subs: [
+            { name: '已完成', value: '1,205 单', change: 6.2 },
+            { name: '在途', value: '135 单', change: 12.0 },
+            { name: '待发运', value: '92 单', change: -4.5 },
+            { name: '异常单', value: '65 单', change: 1.8 },
+          ],
+        },
+        {
+          label: '运输利润',
+          value: '2,058.2',
+          unit: '万元',
+          trend: 15.7,
+          subs: [
+            { name: '利润率', value: '13.7%', change: 1.5 },
+            { name: '单均利润', value: '1.38 万元', change: 5.6 },
+            { name: '燃油成本', value: '8,931 万元', change: -3.2 },
+            { name: '过路费用', value: '4,208 万元', change: 0.9 },
+          ],
+        },
+      ],
+    };
+  },
+};
+</script>
+
+<style lang="scss" scoped>
+@import '../dashboard.scss';
+
+.kpi-card {
+  background: #ffffff;
+  border-radius: 10px;
+  padding: 18px 20px;
+  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.04);
+  margin-bottom: 16px;
+}
+
+.kpi-card__top {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+}
+
+.kpi-card__label {
+  font-size: 13px;
+  color: #909399;
+}
+
+.kpi-card__badge {
+  font-size: 12px;
+  padding: 2px 8px;
+  border-radius: 10px;
+
+  &.is-up {
+    color: #f04747;
+    background: #fdecec;
+  }
+
+  &.is-down {
+    color: #2ba471;
+    background: #e8f7ef;
+  }
+}
+
+.kpi-card__value {
+  font-size: 30px;
+  font-weight: 700;
+  color: #303133;
+  margin: 8px 0 12px;
+}
+
+.kpi-card__unit {
+  font-size: 13px;
+  font-weight: 400;
+  color: #909399;
+  margin-left: 6px;
+}
+
+.kpi-card__subs {
+  list-style: none;
+  margin: 0;
+  padding: 10px 0 0;
+  border-top: 1px solid #f0f2f5;
+
+  li {
+    display: flex;
+    align-items: center;
+    padding: 5px 0;
+    font-size: 13px;
+  }
+}
+
+.kpi-card__sub-name {
+  color: #909399;
+  flex: 1;
+}
+
+.kpi-card__sub-value {
+  color: #303133;
+  font-weight: 600;
+  margin-right: 10px;
+}
+
+.kpi-card__sub-change {
+  width: 56px;
+  text-align: right;
+
+  &.is-up {
+    color: #f04747;
+  }
+
+  &.is-down {
+    color: #2ba471;
+  }
+}
+</style>