Add separate kline.db and pre-seed small-account four-product K-lines on startup.

Co-authored-by: Cursor <cursoragent@cursor.com>

modules/market/kline_store.py

@@ -3,9 +3,10 @@
 # 严禁用于：带单/代客理财、向他人推荐期货品种或买卖建议、融资配资等业务。
 # 详见 LICENSE.zh-CN.txt 与 docs/软件购买与使用协议.md
 
-"""K 线本地 SQLite 缓存。"""
+"""K 线本地 SQLite 缓存（独立库 data/kline.db，与业务 futures.db 分离）。"""
 from __future__ import annotations
 
+import os
 import sqlite3
 from datetime import datetime, timedelta
 from typing import Optional
@@ -27,6 +28,24 @@ REFRESH_SECONDS = {
 }
 
 
+def connect_kline_db(path: Optional[str] = None) -> sqlite3.Connection:
+    """K 线专用 SQLite（生产环境业务库可为 PostgreSQL，K 线仍走本地文件）。"""
+    from modules.core.paths import KLINE_DB_PATH
+
+    db_path = path or KLINE_DB_PATH
+    parent = os.path.dirname(db_path)
+    if parent:
+        os.makedirs(parent, exist_ok=True)
+    conn = sqlite3.connect(db_path, timeout=30, check_same_thread=False)
+    conn.row_factory = sqlite3.Row
+    conn.execute("PRAGMA busy_timeout=30000")
+    try:
+        conn.execute("PRAGMA journal_mode=WAL")
+    except sqlite3.OperationalError:
+        pass
+    return conn
+
+
 def ensure_kline_tables(conn: sqlite3.Connection) -> None:
     conn.execute(
         """CREATE TABLE IF NOT EXISTS kline_bars (