Select-list keyboard handling: text-input options no longer accept on Enter, and edge navigation escapes the list

The select:accept keyboard binding now ignores options of type input and reads the focused value through a getter rather than captured state, so a stale focus can no longer be submitted accidentally. Pressing Down or Up (or ctrl-n/ctrl-p) at the last or first option now calls the list's exit-downward or exit-upward callback and stops propagation, letting focus move out of the list instead of clamping at the edge.