Enable SQLite WAL journaling

src/trader_mcp/strategy_store.py

@@ -44,6 +44,8 @@ def get_connection() -> sqlite3.Connection:
     conn = sqlite3.connect(DB_PATH)
     conn.row_factory = sqlite3.Row
     conn.execute("PRAGMA foreign_keys = ON")
+    conn.execute("PRAGMA journal_mode = WAL")
+    conn.execute("PRAGMA synchronous = NORMAL")
     return conn