Adds a user-configurable spacing between system tray icons in the bar,
available per widget via the tray context menu in Settings > Widgets
("Icon Spacing" stepper, 0-20px), with a global default fallback.
- SettingsData/SettingsSpec: new trayIconSpacing setting (default 0)
- SystemTrayBar: apply configuredIconSpacing to the horizontal Row and
vertical Column layouts, and account for it in auto-overflow item
estimation and drag-and-drop slot math (shift offsets and target
index calculation)
- WidgetsTabSection: "Icon Spacing" stepper in the tray widget context
menu, following the existing "Max Visible" pattern
- WidgetsTab: keep trayIconSpacing when restoring per-widget data
Tássio Virgínio
3b527f1f7f