### 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)
}
		}
		if (!is_transparent(c)) {
			pc = c;
		}
		i++;
	}
	return kashida_pos;
}
bool TextServerAdvanced::_shaped_text_update_justification_ops(const RID &p_shaped) {
	ShapedTextDataAdvanced *sd = shaped_owner.get_or_null(p_shaped);
	ERR_FAIL_COND_V(!sd, false);
	MutexLock lock(sd->mutex);
	if (!sd->valid) {
		_shaped_text_shape(p_shaped);
	}
	if (!sd->line_breaks_valid) {
		_shaped_text_update_breaks(p_shaped);
	}
	if (sd->justification_ops_valid) {
		return true; 
	}
	const UChar *data = sd->utf16.get_data();
	int data_size = sd->utf16.length();
	if (!sd->js_ops_valid) {
		sd->jstops.clear();
		
		UErrorCode err = U_ZERO_ERROR;
		UBreakIterator *bi = ubrk_open(UBRK_WORD, "", data, data_size, &err);
		if (U_FAILURE(err)) {