- Extract isTaskStuck and countStuckTasks into shared utils/taskStuck.ts utility
- Replace hardcoded 10-minute threshold with project taskStuckTimeoutMs setting
- Thread taskStuckTimeoutMs from App settings fetch through ExecutorStatusBar to useExecutorStats
- Return 0 stuck tasks when timeout is undefined/0 (disabled), matching engine behavior
- Update tests to verify disabled state, custom thresholds, and zero threshold edge case