withinPortal:true breaks Mantine Select inside vaul bottom-sheet on mobile

When Mantine <Select comboboxProps={{ withinPortal: true }} /> is mounted inside a vaul <Drawer.Content> on iOS Safari (and likely other touch browsers), the dropdown popup renders as a sibling of the drawer in the DOM (portaled to document.body) rather than inside it. The drawer interprets any touch outside its own content box as a swipe/dismiss gesture and either closes itself or simply eats the touch event before it reaches the popped-out dropdown — so option taps register as nothing. Desktop works fine because mouse events propagate differently than touch + drawer gesture handlers. Fix: switch to withinPortal: false so the popup renders inline inside the drawer DOM tree. The whole-codebase convention in any vaul-bottom-sheet-using app should be withinPortal: false for any Mantine popover/select/menu rendered inside the drawer — even if the desktop version of the same drawer uses portal: true. Easy regression to introduce by copy-pasting Mantine docs which default to withinPortal: true.