The dialog's presentation mode.
When set to `ADAP_DIALOG_AUTO`, the dialog appears as a bottom sheet when the following condition is met: `max-width: 450px or max-height: 360px`, and as a floating window otherwise.
Set it to `ADAP_DIALOG_FLOATING` or `ADAP_DIALOG_BOTTOM_SHEET` to always present it a floating window or a bottom sheet respectively, regardless of available size.
Presentation mode does nothing for dialogs presented as a window.