Add default value for secret_key in config.py to prevent startup crash

config.py

@@ -28,7 +28,7 @@ class Settings(BaseSettings):
     app_name: str = "Aria - Your Spiritual Companion"
     app_version: str = "1.0.0"
     debug: bool = False
-    secret_key: str
+    secret_key: str = "your_secret_key_here"
     algorithm: str = "HS256"
     access_token_expire_minutes: int = 15