pi: cycle models backward with ctrl+n

♠ Previously . Problem statement : pi binds ctrl+p to app.model.cycleForward 1 by default, but has no default binding to cycle backward other than shift+ctrl+p , which is arguably difficult to remember. Every keybinding in pi is namespaced and overridable via ~/.pi/agent/keybindings.json , documented in docs/keybindings.md : { "app.model.cycleBackward": [ "shift+ctrl+p", "ctrl+n" ] } ctrl+n is…