GNOME Argos — Functions Submenu
- Normal-screen layout: moved all 6 functional buttons (Compact Menu, Search, FZF Search, Export, Online Version, GitHub) into a collapsible Functions submenu
- Functions submenu appears before cheatsheet category groups — reclaims top-level Argos dropdown space for categories
- Small-screen layout is unchanged (existing behavior preserved)
- No impact on KDE, XFCE, dialog-based, or terminal DE paths