### 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)
double gla = Math::round(_font_get_glyph_advance(f, fs, w[i + j].index).x * 0.5);
						p_sd->ascent = MAX(p_sd->ascent, gla);
						p_sd->descent = MAX(p_sd->descent, gla);
					}
					p_sd->width += w[i + j].advance;
					w[i + j].start += p_sd->start;
					w[i + j].end += p_sd->start;
					p_sd->glyphs.push_back(w[i + j]);
				}
			} else {
				if (failed_subrun_start >= w[i].start) {
					failed_subrun_start = w[i].start;
				}
				if (failed_subrun_end <= w[i].end) {
					failed_subrun_end = w[i].end;
				}
			}
			i += w[i].count - 1;
		}
		memfree(w);
		if (failed_subrun_start != p_end + 1) {
			_shape_run(p_sd, failed_subrun_start, failed_subrun_end, p_script, p_direction, p_fonts, p_span, p_fb_index + 1, p_start, p_end);
		}
		p_sd->ascent = MAX(p_sd->ascent, _font_get_ascent(f, fs) + _font_get_spacing(f, SPACING_TOP));
		p_sd->descent = MAX(p_sd->descent, _font_get_descent(f, fs) + _font_get_spacing(f, SPACING_BOTTOM));
		p_sd->upos = MAX(p_sd->upos, _font_get_underline_position(f, fs));
		p_sd->uthk = MAX(p_sd->uthk, _font_get_underline_thickness(f, fs));
	}
}
bool TextServerAdvanced::_shaped_text_shape(const RID &p_shaped) {