Fix SyntaxError: move global declarations before variable usage in get_db function

app/db/session.py

@@ -105,10 +105,11 @@ except Exception as e:
 # Dependency to get DB session
 def get_db():
     """FastAPI dependency for database sessions with error handling."""
+    global engine, SessionLocal
+    
     if not SessionLocal:
         logger.error("Database session not initialized, attempting to initialize")
         # Last chance to initialize
-        global engine, SessionLocal
         try:
             engine = create_engine("sqlite://", connect_args={"check_same_thread": False})
             SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)