refactor(vnt-web): 前端重构为 Vite+Vue3+Pinia 工程并重新设计 UI

- 单文件 index.html 拆分为 vnt-web/ui(pnpm+Vite+Vue3 SFC+Pinia+Tailwind v4),构建产物输出到 static/
- UI 重新设计:浅色简洁风(可切换深色模式)、顶部导航、新增总览仪表盘首页
- 自定义弹窗/toast/确认框替换全部原生 alert/confirm,交互与过渡统一
- 响应式布局:移动端汉堡导航,表格与卡片自适应
- 实例卡片移除日志按钮;启动组网默认选中第一个配置

vnt-web/ui/src/components/StartPanel.vue

@@ -0,0 +1,72 @@
+<script setup>
+import { ref, computed, watch } from "vue";
+import { useAppStore } from "../stores/app";
+import { useUiStore } from "../stores/ui";
+
+// 启动组网面板:选择配置 + 启动,总览页与实例页复用
+const app = useAppStore();
+const ui = useUiStore();
+
+const localSelectedConfig = ref("");
+
+// 只列出没有对应实例的配置(同一配置最多一个实例)
+const availableConfigs = computed(() =>
+  app.configList.filter(
+    (cfg) => !app.instanceList.some((inst) => inst.file_name === cfg.file_name),
+  ),
+);
+
+// 默认选中第一个可用配置;当前选中项不可用时(如已启动)自动切到下一个
+watch(
+  availableConfigs,
+  (list) => {
+    if (!list.some((cfg) => cfg.file_name === localSelectedConfig.value)) {
+      localSelectedConfig.value = list.length ? list[0].file_name : "";
+    }
+  },
+  { immediate: true },
+);
+
+const handleStart = () => {
+  if (!localSelectedConfig.value) {
+    ui.toast.error("请先选择一个配置");
+    return;
+  }
+  app.startVnt(localSelectedConfig.value);
+};
+</script>
+
+<template>
+  <div class="card">
+    <h2 class="mb-4 text-base font-bold text-slate-900 dark:text-white">启动组网</h2>
+
+    <div v-if="app.configList.length === 0" class="flex flex-wrap items-center justify-between gap-3">
+      <p class="text-sm muted">还没有任何配置，先创建一个组网配置吧。</p>
+      <router-link to="/config" class="btn-primary btn-sm">去新建配置</router-link>
+    </div>
+
+    <div v-else-if="availableConfigs.length === 0" class="text-sm muted">
+      所有配置均已启动。
+    </div>
+
+    <div v-else class="flex flex-col gap-3 sm:flex-row sm:items-end">
+      <div class="flex-1">
+        <label class="mb-1.5 block text-xs font-medium muted">选择配置</label>
+        <select v-model="localSelectedConfig" class="input">
+          <option value="" disabled>请选择配置...</option>
+          <option v-for="cfg in availableConfigs" :key="cfg.file_name" :value="cfg.file_name">
+            {{ cfg.config_name || cfg.file_name }}
+          </option>
+        </select>
+      </div>
+      <button
+        class="btn-primary px-8"
+        :disabled="!localSelectedConfig || !!app.loadingMap[localSelectedConfig]"
+        @click="handleStart"
+      >
+        <span v-if="app.loadingMap[localSelectedConfig]" class="animate-spin">⟳</span>
+        启动
+      </button>
+    </div>
+  </div>
+</template>