### Godot version

v4.2.dev4.official [549fcce5f]

### System information

Ubuntu 20.04 LTS

### Issue description

See title.

### Steps to reproduce

1. Create a new project
2. Create a csv file that includes the following
```
key,ar
key,placeholder
```
3. Add the generated `.translation` file to Project -> Project Settings... -> Localization
4. In Project -> Project Settings... -> Internationalization -> Locale, set `Test` to `ar`
5. Add a `LineEdit` node and type `-=[]{}`
6. Run the project, and notice that the text is on the right side, but the symbols are incorrectly in LTR (`-=[]{}`).  Correct output is `{}[]=-`
7. Back in the editor, add a single Arabic letter (any will do), and notice that `LineEdit` immediately (and correctly) flips the symbols, and the newly-added Arabic letter, to RTL.

**Notes**
- Identical behavior is seen with `TextEdit`.
- The purpose of steps 2-4 are to simulate an Arabic environment when the project is run, despite `OS.get_locale() == "en"` (or your system's current language).

### Minimal reproduction project

[rtlsymbols.zip](https://github.com/godotengine/godot/files/12525509/rtlsymbols.zip)
MSContext *context = static_cast<MSContext *>(user);
	context->contour->addEdge(new msdfgen::QuadraticSegment(context->position, ft_point2(*control), ft_point2(*to)));
	context->position = ft_point2(*to);
	return 0;
}
static int ft_cubic_to(const FT_Vector *control1, const FT_Vector *control2, const FT_Vector *to, void *user) {
	MSContext *context = static_cast<MSContext *>(user);
	context->contour->addEdge(new msdfgen::CubicSegment(context->position, ft_point2(*control1), ft_point2(*control2), ft_point2(*to)));
	context->position = ft_point2(*to);
	return 0;
}
void TextServerAdvanced::_generateMTSDF_threaded(void *p_td, uint32_t p_y) {
	MSDFThreadData *td = static_cast<MSDFThreadData *>(p_td);
	msdfgen::ShapeDistanceFinder<msdfgen::OverlappingContourCombiner<msdfgen::MultiAndTrueDistanceSelector>> distanceFinder(*td->shape);
	int row = td->shape->inverseYAxis ? td->output->height() - p_y - 1 : p_y;
	for (int col = 0; col < td->output->width(); ++col) {
		int x = (p_y % 2) ? td->output->width() - col - 1 : col;
		msdfgen::Point2 p = td->projection->unproject(msdfgen::Point2(x + .5, p_y + .5));
		msdfgen::MultiAndTrueDistance distance = distanceFinder.distance(p);
		td->distancePixelConversion->operator()(td->output->operator()(x, row), distance);
	}
}
_FORCE_INLINE_ TextServerAdvanced::FontGlyph TextServerAdvanced::rasterize_msdf(FontAdvanced *p_font_data, FontForSizeAdvanced *p_data, int p_pixel_range, int p_rect_margin, FT_Outline *outline, const Vector2 &advance) const {