修复机构落地页构建失败并恢复 Polymarket 市场扫描

InstitutionalLandingPage.tsx 补充 "use client" 指令以通过 Next.js 15 构建。
polymarket_readonly.py 集成 WebSocket 报价缓存加速价格获取。
city_payloads.py 复用 Polymarket 层构建真实市场扫描数据替代空返回。

Constraint: 市场扫描需在无 Polymarket 价格 UI 的前提下提供数据
Tested: npm run build 通过

src/data_collection/polymarket_readonly.py

@@ -4,6 +4,7 @@ Polymarket read-only market layer.
 P0 scope:
 - Market discovery from Gamma REST
 - Price / midpoint / spread / orderbook read from CLOB REST
+- Optional WebSocket quote acceleration via PolymarketWsQuoteCache
 - No signing, no order placement
 """
 
@@ -23,6 +24,7 @@ import httpx
 from loguru import logger
 
 from src.data_collection.city_registry import ALIASES, CITY_REGISTRY
+from src.data_collection.polymarket_ws_cache import PolymarketWsQuoteCache
 
 
 def _safe_float(value: Any) -> Optional[float]:
@@ -448,6 +450,9 @@ class PolymarketReadOnlyLayer:
         self._price_cache: Dict[str, Dict[str, Any]] = {}
         self._lock = threading.Lock()
 
+        self._ws_cache = PolymarketWsQuoteCache.from_env()
+        self._ws_cache.start()
+
     def _market_scan_debug_enabled(self) -> bool:
         return (
             str(os.getenv("POLYMARKET_MARKET_SCAN_DEBUG", "false")).strip().lower()
@@ -1769,6 +1774,14 @@ class PolymarketReadOnlyLayer:
             if cached and now - cached.get("t", 0) < self.price_cache_ttl:
                 return cached.get("data", {})
 
+        ws_data = self._ws_cache.get_market_data(token_id)
+        if ws_data:
+            with self._lock:
+                self._price_cache[token_id] = {"data": ws_data, "t": now}
+            return ws_data
+
+        self._ws_cache.subscribe([token_id])
+
         data = self._fetch_token_market_data(token_id)
 
         with self._lock: