feat(lbs): 真实距离与按距离派单落地

- 数据库：orders/activities 新增 latitude/longitude（含存量表 ALTER 迁移）

- 服务端：Haversine 计算 distanceKm/distanceText，派单池支持 lat/lng/radius 过滤并按距离升序；历史无坐标订单用腾讯地理编码兜底并回写缓存

- 新增 /api/lbs/reverse 逆地址解析（Key 仅服务端持有，登录 + 限流）

- 小程序：雷达/接单大厅改用真实定位与真实距离，删除全部写死演示距离；下单页新增地图选点，组局页保存选点经纬度

- 修复接单大厅点接单会新建订单的问题，改为真正 claimOrder 认领

- 新增 lbs-distance 护栏（110 套件/729 用例全绿）

server/src/index.ts

@@ -489,6 +489,99 @@ function assertCompanionActor(
   throw e;
 }
 
+// ===== 腾讯位置服务（仅服务端调用，Key 绝不下发小程序）=====
+let mapKeyCache: { key: string; at: number } | null = null;
+
+async function resolveTencentMapKey(): Promise<string> {
+  const envKey = String(process.env.TENCENT_MAP_KEY || '').trim();
+  if (envKey) return envKey;
+  const now = Date.now();
+  if (mapKeyCache && now - mapKeyCache.at < 60_000) return mapKeyCache.key;
+  let key = '';
+  try {
+    const record = await repo.getPlatformConfigByKey('map_location_config');
+    const value = (record && record.valueJson) || {};
+    key = String(value.mapKey || '').trim();
+  } catch (e) {
+    logServerError('resolveTencentMapKey', e);
+  }
+  mapKeyCache = { key, at: now };
+  return key;
+}
+
+function httpsGetJson(url: string, timeoutMs = 4000): Promise<any> {
+  return new Promise((resolve, reject) => {
+    const req = https.get(url, (resp) => {
+      let data = '';
+      resp.on('data', (chunk) => {
+        data += chunk;
+      });
+      resp.on('end', () => {
+        try {
+          resolve(JSON.parse(data));
+        } catch (e) {
+          reject(e);
+        }
+      });
+    });
+    req.setTimeout(timeoutMs, () => req.destroy(new Error('腾讯位置服务请求超时')));
+    req.on('error', reject);
+  });
+}
+
+const geocodeCache = new Map<string, { geo: { lat: number; lng: number } | null; at: number }>();
+
+/** 地址 -> 坐标（腾讯 WebService 地理编码），带进程内缓存 */
+async function geocodeAddress(address: string): Promise<{ lat: number; lng: number } | null> {
+  const text = String(address || '').trim();
+  if (!text) return null;
+  const cached = geocodeCache.get(text);
+  if (cached && Date.now() - cached.at < 10 * 60_000) return cached.geo;
+  const key = await resolveTencentMapKey();
+  if (!key) return null;
+  try {
+    const url = `https://apis.map.qq.com/ws/geocoder/v1/?address=${encodeURIComponent(text)}&key=${encodeURIComponent(key)}`;
+    const data = await httpsGetJson(url);
+    if (data && data.status === 0 && data.result && data.result.location) {
+      const geo = { lat: Number(data.result.location.lat), lng: Number(data.result.location.lng) };
+      if (Number.isFinite(geo.lat) && Number.isFinite(geo.lng)) {
+        geocodeCache.set(text, { geo, at: Date.now() });
+        return geo;
+      }
+    }
+    logServerError('geocodeAddress', new Error(`腾讯地理编码失败: ${data && (data.message || data.status)}`));
+    geocodeCache.set(text, { geo: null, at: Date.now() });
+  } catch (e) {
+    logServerError('geocodeAddress', e);
+  }
+  return null;
+}
+
+/** 坐标 -> 行政区/地址（腾讯 WebService 逆地址解析） */
+async function reverseGeocode(lat: number, lng: number): Promise<any | null> {
+  const key = await resolveTencentMapKey();
+  if (!key) return null;
+  try {
+    const url = `https://apis.map.qq.com/ws/geocoder/v1/?location=${lat},${lng}&key=${encodeURIComponent(key)}&get_poi=0`;
+    const data = await httpsGetJson(url);
+    if (data && data.status === 0 && data.result) {
+      const r = data.result;
+      const comp = r.address_component || {};
+      const city = comp.city || '';
+      const district = comp.district || '';
+      return {
+        name: [city, district].filter(Boolean).join(' · ') || r.address || '当前位置',
+        address: r.address || '',
+        latitude: lat,
+        longitude: lng,
+      };
+    }
+  } catch (e) {
+    logServerError('reverseGeocode', e);
+  }
+  return null;
+}
+
 // 管理端：吊销所有后台登录态（版本号 +1，所有已签发 admin token 立即失效）
 app.post('/api/admin/session/revoke-all', requireAdmin, async (req: Request, res: Response) => {
   try {
@@ -1381,15 +1474,54 @@ app.get('/api/orders', async (req: Request, res: Response) => {
 });
 
 // 获取即时可抢订单池 (落盘 MySQL)
-app.get('/api/orders/pool', async (_req: Request, res: Response) => {
+app.get('/api/orders/pool', async (req: Request, res: Response) => {
   try {
-    const list = await repo.getOrdersPool();
+    const lat = Number(req.query.lat);
+    const lng = Number(req.query.lng);
+    const radius = Number(req.query.radius);
+    const hasFrom = Number.isFinite(lat) && Number.isFinite(lng) && Math.abs(lat) <= 90 && Math.abs(lng) <= 180 && !(lat === 0 && lng === 0);
+
+    // 先取不带半径的全量池：为历史无坐标订单做地理编码兜底（每轮最多 5 条，结果回写入库）
+    let pre = await repo.getOrdersPool(hasFrom ? { fromLat: lat, fromLng: lng } : {});
+    if (hasFrom) {
+      const missing = pre.filter((o: any) => !o.hasGeo && o.location).slice(0, 5);
+      let changed = false;
+      for (const o of missing) {
+        const geo = await geocodeAddress(o.location);
+        if (geo) {
+          await repo.updateOrderGeo(o.id, geo.lat, geo.lng);
+          changed = true;
+        }
+      }
+      if (changed) pre = await repo.getOrdersPool({ fromLat: lat, fromLng: lng });
+    }
+
+    const list = hasFrom && Number.isFinite(radius) && radius > 0
+      ? pre.filter((o: any) => o.distanceKm !== null && o.distanceKm <= radius)
+      : pre;
     res.json({ code: 20000, data: list });
   } catch (err: any) {
     res.status(500).json({ code: 50000, message: err.message });
   }
 });
 
+// 坐标反查行政区/地址（雷达/接单大厅顶部定位文案；仅登录用户可调用，避免刷额度）
+app.get('/api/lbs/reverse', rateLimit({ name: 'lbs_reverse', windowMs: 60 * 1000, max: 30, key: rateWriteKey }), async (req: Request, res: Response) => {
+  try {
+    if (SECURE_MODE) resolveSecureUserId(req, Number(req.query.userId || 0), '解析当前位置');
+    const lat = Number(req.query.lat);
+    const lng = Number(req.query.lng);
+    if (!Number.isFinite(lat) || !Number.isFinite(lng) || Math.abs(lat) > 90 || Math.abs(lng) > 180) {
+      return res.status(400).json({ code: 40000, message: '经纬度参数不合法' });
+    }
+    const data = await reverseGeocode(lat, lng);
+    res.json({ code: 20000, data });
+  } catch (err: any) {
+    const statusCode = err.status || 500;
+    res.status(statusCode).json({ code: err.code || 50000, message: err.message });
+  }
+});
+
 // 大神抢单/接单认领 (落盘 MySQL)
 app.post('/api/orders/:id/claim', async (req: Request, res: Response) => {
   try {