Title: Workflow simulation stuck in "Working" state - stop button not responding

Description:

Steps to reproduce: Started workflow simulation, it shows "Working" status for 2-3 days, clicking stop button has no effect

Expected behavior: Stop button should end the simulation

Actual behavior: Simulation remains stuck in "Working" state despite clicking stop

Impact: Causing work limitations and disruptions

Troubleshooting tried: Restarted simulation with rewind-clock icon, refreshed browser, closed other tabs - none worked