Claude Code: Fix import paths in error_handlers.py

- Use 'from agents import brain_minimal' (matching app.py pattern)
- Use brain_minimal.get_brain() factory function instead of direct class instantiation
- This ensures proper module resolution in Docker runtime environment

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

error_handlers.py

@@ -148,9 +148,9 @@ def handle_brain_response(message: str) -> str:
     try:
         # Import openclaw first to set up sys.path, then import agents
         import openclaw
-        from agents.brain_minimal import BrainMinimal
+        from agents import brain_minimal
 
-        brain = BrainMinimal(agent_name="cain", legacy_mode=True)
+        brain = brain_minimal.get_brain(agent_name="cain", legacy_mode=True)
         result = brain._conversation_process(message)
 
         if result.get("success"):