### 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
Control::_update_theme_item_cache();
	theme_cache.base_scale = get_theme_default_base_scale();
	
	theme_cache.brace_mismatch_color = get_theme_color(SNAME("brace_mismatch_color"), SNAME("CodeEdit"));
	theme_cache.code_folding_color = get_theme_color(SNAME("code_folding_color"), SNAME("CodeEdit"));
	theme_cache.folded_eol_icon = get_theme_icon(SNAME("folded_eol_icon"), SNAME("CodeEdit"));
	
	theme_cache.search_result_color = get_theme_color(SNAME("search_result_color"));
	theme_cache.search_result_border_color = get_theme_color(SNAME("search_result_border_color"));
	
	theme_cache.caret_width = get_theme_constant(SNAME("caret_width"));
	theme_cache.caret_color = get_theme_color(SNAME("caret_color"));
	theme_cache.caret_background_color = get_theme_color(SNAME("caret_background_color"));
	
	theme_cache.font_selected_color = get_theme_color(SNAME("font_selected_color"));
	theme_cache.selection_color = get_theme_color(SNAME("selection_color"));
	use_selected_font_color = theme_cache.font_selected_color != Color(0, 0, 0, 0);
	
	theme_cache.style_normal = get_theme_stylebox(SNAME("normal"));
	theme_cache.style_focus = get_theme_stylebox(SNAME("focus"));
	theme_cache.style_readonly = get_theme_stylebox(SNAME("read_only"));
	theme_cache.tab_icon = get_theme_icon(SNAME("tab"));
	theme_cache.space_icon = get_theme_icon(SNAME("space"));
	theme_cache.font = get_theme_font(SNAME("font"));
	theme_cache.font_size = get_theme_font_size(SNAME("font_size"));
	theme_cache.font_color = get_theme_color(SNAME("font_color"));
	theme_cache.font_readonly_color = get_theme_color(SNAME("font_readonly_color"));
	theme_cache.font_placeholder_color = get_theme_color(SNAME("font_placeholder_color"));