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

backend/apps/frontend_service.py

@@ -81,7 +81,12 @@ async def proxy_ws(ws: WebSocket):
     await ws.accept()
     upstream = None
     try:
-        upstream = await websockets.asyncio.client.connect(gateway_url)
+        upstream = await websockets.asyncio.client.connect(
+            gateway_url,
+            ping_interval=20,
+            ping_timeout=120,
+            max_size=10 * 1024 * 1024,  # 10MB
+        )
 
         async def client_to_upstream():
             try:

backend/apps/news_service.py

@@ -28,11 +28,11 @@ def create_app() -> FastAPI:
     add_cors_middleware(app)
 
     @app.get("/health")
-    async def health_check() -> dict[str, str]:
+    def health_check() -> dict[str, str]:
         return {"status": "healthy", "service": "news-service"}
 
     @app.get("/api/enriched-news")
-    async def api_get_enriched_news(
+    def api_get_enriched_news(
         ticker: str = Query(..., min_length=1),
         start_date: str | None = Query(None),
         end_date: str | None = Query(None),
@@ -49,7 +49,7 @@ def create_app() -> FastAPI:
         )
 
     @app.get("/api/news-for-date")
-    async def api_get_news_for_date(
+    def api_get_news_for_date(
         ticker: str = Query(..., min_length=1),
         date: str = Query(...),
         limit: int = Query(20, ge=1, le=100),
@@ -64,7 +64,7 @@ def create_app() -> FastAPI:
         )
 
     @app.get("/api/news-timeline")
-    async def api_get_news_timeline(
+    def api_get_news_timeline(
         ticker: str = Query(..., min_length=1),
         start_date: str = Query(...),
         end_date: str = Query(...),
@@ -79,7 +79,7 @@ def create_app() -> FastAPI:
         )
 
     @app.get("/api/categories")
-    async def api_get_categories(
+    def api_get_categories(
         ticker: str = Query(..., min_length=1),
         start_date: str | None = Query(None),
         end_date: str | None = Query(None),
@@ -96,7 +96,7 @@ def create_app() -> FastAPI:
         )
 
     @app.get("/api/similar-days")
-    async def api_get_similar_days(
+    def api_get_similar_days(
         ticker: str = Query(..., min_length=1),
         date: str = Query(...),
         n_similar: int = Query(5, ge=1, le=20),
@@ -111,7 +111,7 @@ def create_app() -> FastAPI:
         )
 
     @app.get("/api/stories/{ticker}")
-    async def api_get_story(
+    def api_get_story(
         ticker: str,
         as_of_date: str = Query(...),
         store: MarketStore = Depends(get_market_store),
@@ -124,7 +124,7 @@ def create_app() -> FastAPI:
         )
 
     @app.get("/api/range-explain")
-    async def api_get_range_explain(
+    def api_get_range_explain(
         ticker: str = Query(..., min_length=1),
         start_date: str = Query(...),
         end_date: str = Query(...),

backend/apps/trading_service.py

@@ -29,12 +29,12 @@ def create_app() -> FastAPI:
     add_cors_middleware(app)
 
     @app.get("/health")
-    async def health_check() -> dict[str, str]:
+    def health_check() -> dict[str, str]:
         """Health check endpoint."""
         return {"status": "healthy", "service": "trading-service"}
 
     @app.get("/api/prices", response_model=PriceResponse)
-    async def api_get_prices(
+    def api_get_prices(
         ticker: str = Query(..., min_length=1),
         start_date: str = Query(...),
         end_date: str = Query(...),
@@ -47,7 +47,7 @@ def create_app() -> FastAPI:
         return PriceResponse(ticker=payload["ticker"], prices=payload["prices"])
 
     @app.get("/api/financials", response_model=FinancialMetricsResponse)
-    async def api_get_financials(
+    def api_get_financials(
         ticker: str = Query(..., min_length=1),
         end_date: str = Query(...),
         period: str = Query("ttm"),
@@ -62,7 +62,7 @@ def create_app() -> FastAPI:
         return FinancialMetricsResponse(financial_metrics=payload["financial_metrics"])
 
     @app.get("/api/news", response_model=CompanyNewsResponse)
-    async def api_get_news(
+    def api_get_news(
         ticker: str = Query(..., min_length=1),
         end_date: str = Query(...),
         start_date: str | None = Query(None),
@@ -77,7 +77,7 @@ def create_app() -> FastAPI:
         return CompanyNewsResponse(news=payload["news"])
 
     @app.get("/api/insider-trades", response_model=InsiderTradeResponse)
-    async def api_get_insider_trades(
+    def api_get_insider_trades(
         ticker: str = Query(..., min_length=1),
         end_date: str = Query(...),
         start_date: str | None = Query(None),
@@ -92,12 +92,12 @@ def create_app() -> FastAPI:
         return InsiderTradeResponse(insider_trades=payload["insider_trades"])
 
     @app.get("/api/market/status")
-    async def api_get_market_status() -> dict[str, Any]:
+    def api_get_market_status() -> dict[str, Any]:
         """Return current market status using the existing market service logic."""
         return trading_domain.get_market_status_payload()
 
     @app.get("/api/market-cap")
-    async def api_get_market_cap(
+    def api_get_market_cap(
         ticker: str = Query(..., min_length=1),
         end_date: str = Query(...),
     ) -> dict[str, Any]:
@@ -108,7 +108,7 @@ def create_app() -> FastAPI:
         )
 
     @app.get("/api/line-items", response_model=LineItemResponse)
-    async def api_get_line_items(
+    def api_get_line_items(
         ticker: str = Query(..., min_length=1),
         line_items: list[str] = Query(...),
         end_date: str = Query(...),