### 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)
gl.count = 1;
									if (sd->orientation == ORIENTATION_HORIZONTAL) {
										gl.y_off = sd_glyphs[i].y_off;
									} else {
										gl.x_off = sd_glyphs[i].x_off;
									}
									gl.flags |= GRAPHEME_IS_ELONGATION | GRAPHEME_IS_VIRTUAL;
									sd->glyphs.insert(i, gl);
									i++;
									
									sd_size = sd->glyphs.size();
									sd_glyphs = sd->glyphs.ptrw();
									continue;
								}
							}
						}
					} else if ((sd_glyphs[i].flags & GRAPHEME_IS_SPACE) != GRAPHEME_IS_SPACE && (sd_glyphs[i].flags & GRAPHEME_IS_PUNCTUATION) != GRAPHEME_IS_PUNCTUATION) {
						int count = sd_glyphs[i].count;
						
						if (sd_glyphs[i].end == sd->end) {
							continue;
						}
						
						if (sd_glyphs[i].flags & GRAPHEME_IS_RTL) {
							if ((i + count < sd_size - 1) && ((sd_glyphs[i + count].flags & (GRAPHEME_IS_SPACE | GRAPHEME_IS_BREAK_SOFT)) == (GRAPHEME_IS_SPACE | GRAPHEME_IS_BREAK_SOFT))) {
								continue;
							}
						} else {
							if ((i > 0) && ((sd_glyphs[i - 1].flags & (GRAPHEME_IS_SPACE | GRAPHEME_IS_BREAK_SOFT)) == (GRAPHEME_IS_SPACE | GRAPHEME_IS_BREAK_SOFT))) {
								continue;