feat: 市场看板 - 聚合同花顺SDK全量数据的A股实时看板

- 新增 /dashboard 页面：暗色主题，指数行情/市场温度/涨跌分布/行业强度/概念热度/事件情报
- 后端聚合接口 /api/market-dashboard，30秒缓存
- 利用SDK接口：指数行情、全市场快照、涨停/跌停/炸板池、连板天梯、热门股、飙升榜、龙虎榜、异动分析、集合竞价基准、行业/概念目录
- 市场温度评分：6因子加权（涨跌比/中位涨跌/强弱比/涨停活跃度/炸板惩罚/竞价信号）
- 首页添加市场看板导航入口

src/lib/market-dashboard-api.ts

@@ -0,0 +1,104 @@
+// 市场看板数据 API 客户端
+import { getApiBaseUrl } from "@/lib/api-client";
+
+export interface MarketIndex {
+  code: string;
+  name: string;
+  price: number;
+  change: number;
+  changePct: number;
+  prevClose: number;
+  turnover: number;
+}
+
+export interface MarketTemperature {
+  score: number;
+  label: string;
+  factors: {
+    advanceScore: number;
+    medianScore: number;
+    strongScore: number;
+    limitScore: number;
+    breakPenalty: number;
+    auctionBonus: number;
+  };
+}
+
+export interface AuctionData {
+  score: number;
+  label: string;
+  date: string;
+  benchmark: Record<string, unknown>;
+}
+
+export interface MarketStats {
+  upCount: number;
+  downCount: number;
+  flatCount: number;
+  total: number;
+  marketBreadth: number;
+  medianChange: number;
+  strongCount: number;
+  weakCount: number;
+  limitUp: number;
+  limitDown: number;
+  limitBreak: number;
+  breakRate: number;
+  totalTurnover: number;
+  temperature: MarketTemperature;
+  auction: AuctionData;
+  auctionSignal: string;
+}
+
+export interface SectorStrengthItem {
+  code: string;
+  name: string;
+  price: number;
+  change: number;
+  changePct: number;
+  strength: number;
+  breadthPct: number;
+  strongCount: number;
+}
+
+export interface ConceptStrengthItem {
+  code: string;
+  name: string;
+  changePct: number;
+}
+
+export interface DashboardEvent {
+  type: string;
+  label: string;
+  name: string;
+  code: string;
+  detail: string;
+}
+
+export interface MarketDashboardData {
+  indices: MarketIndex[];
+  marketStats: MarketStats;
+  sectorStrength: SectorStrengthItem[];
+  conceptStrength: ConceptStrengthItem[];
+  events: DashboardEvent[];
+  updateTime: string;
+}
+
+export async function fetchMarketDashboard(): Promise<MarketDashboardData> {
+  const baseUrl = getApiBaseUrl();
+  const resp = await fetch(`${baseUrl}/api/market-dashboard`, {
+    method: "GET",
+    cache: "no-store",
+  });
+  if (!resp.ok) {
+    try {
+      const err = await resp.json();
+      throw new Error(err.detail || `请求失败 (${resp.status})`);
+    } catch (e) {
+      if (e instanceof Error) throw e;
+      throw new Error(`请求失败 (${resp.status})`);
+    }
+  }
+  const result = await resp.json();
+  return result.data;
+}