Function minimal_multi_select_internal 

fn minimal_multi_select_internal<T, D, P, S>(
    items: Vec<T>,
    display_text: D,
    preview_text: P,
    has_preview: bool,
    search_text: S,
) -> Result<Option<Vec<T>>>
where
    D: FnMut(&T) -> String,
    P: FnMut(&T) -> Option<String>,
    S: FnMut(&T) -> String,