### 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)
FontAdvanced *fd = font_owner.get_or_null(p_font_rid);
	ERR_FAIL_COND(!fd);
	MutexLock lock(fd->mutex);
	Vector2i size = _get_size_outline(fd, p_size);
	ERR_FAIL_COND(!_ensure_cache_for_size(fd, size));
#ifdef MODULE_FREETYPE_ENABLED
	int32_t idx = p_index & 0xffffff; 
	if (fd->cache[size]->face) {
		if (fd->msdf) {
			_ensure_glyph(fd, size, (int32_t)idx);
		} else {
			for (int aa = 0; aa < ((fd->antialiasing == FONT_ANTIALIASING_LCD) ? FONT_LCD_SUBPIXEL_LAYOUT_MAX : 1); aa++) {
				if ((fd->subpixel_positioning == SUBPIXEL_POSITIONING_ONE_QUARTER) || (fd->subpixel_positioning == SUBPIXEL_POSITIONING_AUTO && size.x <= SUBPIXEL_POSITIONING_ONE_QUARTER_MAX_SIZE)) {
					_ensure_glyph(fd, size, (int32_t)idx | (0 << 27) | (aa << 24));
					_ensure_glyph(fd, size, (int32_t)idx | (1 << 27) | (aa << 24));
					_ensure_glyph(fd, size, (int32_t)idx | (2 << 27) | (aa << 24));
					_ensure_glyph(fd, size, (int32_t)idx | (3 << 27) | (aa << 24));
				} else if ((fd->subpixel_positioning == SUBPIXEL_POSITIONING_ONE_HALF) || (fd->subpixel_positioning == SUBPIXEL_POSITIONING_AUTO && size.x <= SUBPIXEL_POSITIONING_ONE_HALF_MAX_SIZE)) {
					_ensure_glyph(fd, size, (int32_t)idx | (1 << 27) | (aa << 24));
					_ensure_glyph(fd, size, (int32_t)idx | (0 << 27) | (aa << 24));
				} else {
					_ensure_glyph(fd, size, (int32_t)idx | (aa << 24));
				}
			}
		}
	}
#endif
}
void TextServerAdvanced::_font_draw_glyph(const RID &p_font_rid, const RID &p_canvas, int64_t p_size, const Vector2 &p_pos, int64_t p_index, const Color &p_color) const {