### 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)
int limit = 0;
			for (int i = 0; i < sd->text.length(); i++) {
				if (is_whitespace(data[i])) {
					int ks = _generate_kashida_justification_opportunies(sd->text, limit, i) + sd->start;
					if (ks != -1) {
						sd->jstops[ks] = true;
					}
					limit = i + 1;
				}
			}
			int ks = _generate_kashida_justification_opportunies(sd->text, limit, sd->text.length()) + sd->start;
			if (ks != -1) {
				sd->jstops[ks] = true;
			}
		} else {
			int limit = 0;
			while (ubrk_next(bi) != UBRK_DONE) {
				if (ubrk_getRuleStatus(bi) != UBRK_WORD_NONE) {
					int i = _convert_pos(sd, ubrk_current(bi));
					sd->jstops[i + sd->start] = false;
					int ks = _generate_kashida_justification_opportunies(sd->text, limit, i);
					if (ks != -1) {
						sd->jstops[ks + sd->start] = true;
					}
					limit = i;
				}
			}
			ubrk_close(bi);
		}