Replace the single current-state hero + option rows with two selectable
launcher-mark cards (Calendula / Calendar), so the user sees what each choice
would look like, not just the current name. Tapping a card applies immediately
and highlights it (primary border + tinted container + check); the picker stays
open so the change is visible, and back exits — which also fixes the earlier
"hero doesn't update until reopened" gap.
Built on FullScreenPicker directly (the component OptionPicker wraps) to render
the custom card row; material-3 tokens throughout (surfaceContainerHigh /
primary / primaryContainer / outlineVariant, 24dp corners, 8dp-grid spacing).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>