With a rack selected (or under the cursor), 1-4 assign modes, 5-9 fire root one-shot actions on the primary machine, and Enter/e open its context menu. Numpad works for modes; both frontends share the map. Defense: implements context-menu.md selection-hotkeys clause and machine-work multi-select keyboard surface — thin keyboard over the same human_menu / available_actions source; no new sim verbs.