fix(tabs): refresh tab highlight on monitor focus change

[sim590]

Summary

• Fix tab bar active highlight not updating when switching monitors with focusmonitor or hy3:movefocus monitor:
• When switching away from a monitor, the active tab kept its highlight; when switching back, the highlight was lost until manually moving focus with movefocus

Root cause

Desktop::focusState()->monitor() is not yet updated when tab bars are recalculated during a monitor focus change. This caused active_monitor to be computed against the stale (previous) monitor value, producing inverted highlight behavior.

Fix

• Track the focused monitor internally via g_focusedMonitor, updated from the monitor.focused event
• Use g_focusedMonitor instead of Desktop::focusState()->monitor() in updateNodeList() to compute active_monitor
• Trigger updateDecos() on all monitors when the focused monitor changes, so both the old and new monitor tab bars refresh correctly

[sim590]

Update: Also include special workspaces (scratchpad) in the tab bar refresh loop. Previously, tabs inside a special workspace were not updated on monitor focus change because the listener only iterated over m_activeWorkspace and missed m_activeSpecialWorkspace.