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-finance.vue

@@ -0,0 +1,68 @@
+<template>
+  <section class="wel-sec">
+    <div class="wel-sec__head">
+      <span class="wel-sec__title">财务情况</span>
+      <wel-filters condition-label="核算口径" />
+    </div>
+
+    <div class="wel-card finance-panel">
+      <div class="panel-title">
+        营业收支对比
+        <span class="panel-title__unit">万元</span>
+      </div>
+      <wel-chart :option="barOpt" height="300px" />
+    </div>
+
+    <div class="wel-card finance-panel">
+      <div class="panel-title">
+        主营业务收入/费用趋势
+        <span class="panel-title__unit">万元</span>
+      </div>
+      <wel-chart :option="lineOpt" height="280px" />
+    </div>
+  </section>
+</template>
+
+<script>
+import WelChart from './wel-chart.vue';
+import WelFilters from './wel-filters.vue';
+import { groupBarOption, lineAreaOption } from '../chart-options';
+
+export default {
+  name: 'section-finance',
+  components: { WelChart, WelFilters },
+  data() {
+    const months = Array.from({ length: 12 }, (_, i) => `${i + 1}月`);
+    return {
+      months,
+      // Mock：财务收支数据，对接统计接口后替换
+      incomeData: [2860, 1520, 1180, 1150, 980, 920, 760, 720, 690, 520, 380, 260],
+      costData: [2410, 1330, 1010, 980, 850, 800, 660, 630, 610, 470, 340, 230],
+      trendIncome: [1780, 1850, 1810, 1880, 1920, 1950, 1720, 1650, 1830, 1900, 1980, 2060],
+      trendCost: [1520, 1560, 1540, 1590, 1610, 1620, 1450, 1400, 1530, 1580, 1640, 1700],
+    };
+  },
+  computed: {
+    barOpt() {
+      return groupBarOption(this.months, [
+        { name: '收入', data: this.incomeData, color: '#4a90e2' },
+        { name: '费用', data: this.costData, color: '#d9dce3' },
+      ]);
+    },
+    lineOpt() {
+      return lineAreaOption(this.months, [
+        { name: '主营业务收入', data: this.trendIncome, color: '#4a90e2' },
+        { name: '主营业务费用', data: this.trendCost, color: '#2bb3a3' },
+      ]);
+    },
+  },
+};
+</script>
+
+<style lang="scss" scoped>
+@import '../dashboard.scss';
+
+.finance-panel {
+  margin-bottom: 16px;
+}
+</style>