### 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)
ShapedTextDataAdvanced *parent = shaped_owner.get_or_null(p_shaped->parent);
	for (const KeyValue<Variant, ShapedTextDataAdvanced::EmbeddedObject> &E : parent->objects) {
		if (E.value.pos >= p_shaped->start && E.value.pos < p_shaped->end) {
			p_shaped->objects[E.key] = E.value;
		}
	}
	for (int i = 0; i < parent->spans.size(); i++) {
		ShapedTextDataAdvanced::Span span = parent->spans[i];
		if (span.start >= p_shaped->end || span.end <= p_shaped->start) {
			continue;
		}
		span.start = MAX(p_shaped->start, span.start);
		span.end = MIN(p_shaped->end, span.end);
		p_shaped->spans.push_back(span);
	}
	p_shaped->parent = RID();
}
RID TextServerAdvanced::_create_shaped_text(TextServer::Direction p_direction, TextServer::Orientation p_orientation) {
	_THREAD_SAFE_METHOD_
	ERR_FAIL_COND_V_MSG(p_direction == DIRECTION_INHERITED, RID(), "Invalid text direction.");
	ShapedTextDataAdvanced *sd = memnew(ShapedTextDataAdvanced);
	sd->hb_buffer = hb_buffer_create();
	sd->direction = p_direction;
	sd->orientation = p_orientation;
	return shaped_owner.make_rid(sd);
}
void TextServerAdvanced::_shaped_text_clear(const RID &p_shaped) {