## Summary
- Set `accent="blue"` on InformationBanner action button so it renders
blue instead of default gray
- Add Banner storybook stories for all color × variant combinations
(BluePrimary, BlueSecondary, DangerPrimary, DangerSecondary)
- Use `useUserTimezone()` in `SettingsDatePickerInput` instead of
browser timezone (`Temporal.Now.timeZoneId()`) so dates respect the
admin's profile timezone preference
- Separate `onChange` from `onClose` in `SettingsDatePickerInput` so
changing the hour no longer forces the date picker to close
