Fix AttributeError: Add missing flow_reverse and flow_solver parameters

- Added flow_reverse parameter (default: True) based on config.py defaults
- Added flow_solver parameter (default: "euler") based on config.py defaults
- These parameters are required by FlowMatchDiscreteScheduler initialization

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

app.py

@@ -91,6 +91,12 @@ def create_args():
     args.text_states_dim = 4096
     args.text_states_dim_2 = 768
     
+    # Add missing flow_reverse attribute (default is True based on config.py)
+    args.flow_reverse = True
+    
+    # Add missing flow_solver attribute (default is "euler" based on config.py)
+    args.flow_solver = "euler"
+    
     return args
 
 logger.info("Initializing Hunyuan-GameCraft model...")