feat(api): real klines/trades from indexer + auto table creation

- charts.py: serve OHLCV bars & trades from Postgres (klines/trades tables written by indexer), no synthetic data
- entities.py: add TradeModel/KlineModel matching indexer schema
- main.py: idempotent create_all on startup
- config.py: unify default DATABASE_URL with docker-compose/indexer

app/main.py

@@ -4,6 +4,9 @@ from fastapi import FastAPI, WebSocket, WebSocketDisconnect
 from fastapi.middleware.cors import CORSMiddleware
 from app.config import settings
 from app.api.routes.api import api_router
+from app.api.routes.charts import kline_router
+from app.api.dependencies import engine
+from app.models.entities import Base
 from app.ws.manager import ws_manager
 
 logging.basicConfig(level=logging.INFO, format="%(asctime)s [%(levelname)s] %(name)s: %(message)s")
@@ -12,8 +15,16 @@ logger = logging.getLogger("WTFX-Backend")
 @asynccontextmanager
 async def lifespan(app: FastAPI):
     logger.info(f"Starting {settings.PROJECT_NAME} v{settings.VERSION} [{settings.ENVIRONMENT}]")
+    # 幂等建表（含 Indexer 写入的 klines/trades），避免依赖外部建表步骤
+    try:
+        async with engine.begin() as conn:
+            await conn.run_sync(Base.metadata.create_all)
+        logger.info("Database tables ensured.")
+    except Exception as e:
+        logger.error(f"Failed to ensure database tables: {e}")
     yield
     logger.info("Shutting down WTFX Backend service...")
+    await engine.dispose()
 
 app = FastAPI(
     title=settings.PROJECT_NAME,
@@ -33,6 +44,7 @@ app.add_middleware(
 
 # 注册 API 路由
 app.include_router(api_router, prefix="/api")
+app.include_router(kline_router, prefix="/api")
 
 # WebSocket 实时订阅端点
 @app.websocket("/ws/market/{market_address}")