### Godot version

4.1

### System information

Windows

### Issue description

Being able to have multiple cursors similarly to vscode is a great feature, however it's only possible to add carets, not remove them. By left clicking you can remove all extra cursors but you cannot remove a specific one so after selecting multiple lines a single missclick, you have to reselect them all again. Looking at the original pr there was a remove_caret function added so it would make sense to be able to remove carets when clicking again, like in vscode.

![image](https://github.com/godotengine/godot/assets/19669673/3867c00e-9faa-4429-9c6d-f2d6d3883044)


### Steps to reproduce

- Alt click to add multiple carets
- Alt click on the same position again
- Nothing happens

### Minimal reproduction project

N/A
if (k->is_action("ui_menu", true)) {
			if (context_menu_enabled) {
				_update_context_menu();
				adjust_viewport_to_caret();
				menu->set_position(get_screen_position() + get_caret_draw_pos());
				menu->reset_size();
				menu->popup();
				menu->grab_focus();
			}
			accept_event();
			return;
		}
		if (k->is_action("ui_text_toggle_insert_mode", true)) {
			set_overtype_mode_enabled(!overtype_mode);
			accept_event();
			return;
		}
		if (k->is_action("ui_swap_input_direction", true)) {
			_swap_current_input_direction();
			accept_event();
			return;
		}
		
		k = k->duplicate();
		bool shift_pressed = k->is_shift_pressed();
		
		k->set_shift_pressed(false);
		
		if (k->is_action("ui_text_caret_word_left", true)) {
			_move_caret_left(shift_pressed, true);