Update app.py

app.py

@@ -717,7 +717,7 @@ async def system_health():
     }
     
     # Add module-specific health if available
-    diagnostics_module = module_manager.get_module("diagnostics")
+    diagnostics_module = module_manager.get_module("system_diagnostics")
     if diagnostics_module and hasattr(diagnostics_module, 'get_health'):
         try:
             module_health = await diagnostics_module.get_health()