enforceCursorLimits

pub fn enforceCursorLimits(self: *KeyboardNavigation) void {
        if (self.num_cols > 0)
            self.cursor.col_num = @min(self.cursor.col_num, self.num_cols - 1)
        else
            self.cursor.col_num = 0;
        if (self.num_rows > 0)
            self.cursor.row_num = @min(self.cursor.row_num, self.num_rows - 1)
        else
            self.cursor.row_num = 0;
    }