fix: use relative data dir for Hugging Face Spaces write permission

database.py

@@ -3,10 +3,11 @@ from sqlalchemy.ext.declarative import declarative_base
 from sqlalchemy.orm import sessionmaker
 import os
 
-# 將 data 資料夾建立在專案根目錄
-DB_DIR = os.path.join(os.path.dirname(__file__), "data")
+
+DB_DIR = "data"
 os.makedirs(DB_DIR, exist_ok=True)
 
+
 # 資料庫 URL
 SQLALCHEMY_DATABASE_URL = f"sqlite:///{os.path.join(DB_DIR, 'health_assistant.db')}"