perf: optimize system concurrency, I/O stability and fix WebSocket disconnects

backend/data/market_store.py

@@ -190,8 +190,9 @@ class MarketStore:
         name: str | None = None,
         sector: str | None = None,
         is_active: bool = True,
-    ) -> None:
+    ) -> int:
         timestamp = _utc_timestamp()
+        count = 0
         with self._connect() as conn:
             conn.execute(
                 """
@@ -206,6 +207,8 @@ class MarketStore:
                 """,
                 (symbol, name, sector, 1 if is_active else 0, timestamp, timestamp),
             )
+            count += 1
+        return count
 
     def update_fetch_watermark(
         self,
@@ -213,8 +216,9 @@ class MarketStore:
         symbol: str,
         price_date: str | None = None,
         news_date: str | None = None,
-    ) -> None:
+    ) -> int:
         timestamp = _utc_timestamp()
+        count = 0
         with self._connect() as conn:
             conn.execute(
                 """
@@ -227,6 +231,8 @@ class MarketStore:
                 """,
                 (symbol, timestamp, timestamp, price_date, news_date),
             )
+            count += 1
+        return count
 
     def get_ticker_watermarks(self, symbol: str) -> dict[str, Any]:
         with self._connect() as conn:
@@ -263,6 +269,8 @@ class MarketStore:
         count = 0
         with self._connect() as conn:
             for row in rows:
+                if not row.get("date"):
+                    continue
                 conn.execute(
                     """
                     INSERT INTO ohlc
@@ -341,6 +349,7 @@ class MarketStore:
                         timestamp,
                     ),
                 )
+                count += 1
                 for ticker in tickers:
                     conn.execute(
                         """
@@ -349,7 +358,6 @@ class MarketStore:
                         """,
                         (news_id, str(ticker).strip().upper()),
                     )
-                count += 1
         return count
 
     def get_news_without_trade_date(self, symbol: str | None = None, *, limit: int = 5000) -> list[dict[str, Any]]:
@@ -928,8 +936,9 @@ class MarketStore:
         as_of_date: str,
         content: str,
         source: str = "local",
-    ) -> None:
+    ) -> int:
         timestamp = _utc_timestamp()
+        count = 0
         with self._connect() as conn:
             conn.execute(
                 """
@@ -943,6 +952,8 @@ class MarketStore:
                 """,
                 (symbol, as_of_date, content, source, timestamp, timestamp),
             )
+            count += 1
+        return count
 
     def delete_story_cache(
         self,
@@ -1002,8 +1013,9 @@ class MarketStore:
         target_date: str,
         payload: dict[str, Any],
         source: str = "local",
-    ) -> None:
+    ) -> int:
         timestamp = _utc_timestamp()
+        count = 0
         with self._connect() as conn:
             conn.execute(
                 """
@@ -1017,6 +1029,8 @@ class MarketStore:
                 """,
                 (symbol, target_date, _json_dumps(payload), source, timestamp, timestamp),
             )
+            count += 1
+        return count
 
     def delete_similar_day_cache(
         self,