### 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)
switch (static_cast<TextServer::Direction>(sd->bidi_override[ov].z)) {
				case DIRECTION_LTR: {
					ubidi_setPara(bidi_iter, data + start, end - start, UBIDI_LTR, nullptr, &err);
				} 
				case DIRECTION_RTL: {
					ubidi_setPara(bidi_iter, data + start, end - start, UBIDI_RTL, nullptr, &err);
				} 
				case DIRECTION_INHERITED: {
					ubidi_setPara(bidi_iter, data + start, end - start, sd->base_para_direction, nullptr, &err);
				} 
				case DIRECTION_AUTO: {
					UBiDiDirection direction = ubidi_getBaseDirection(data + start, end - start);
					if (direction != UBIDI_NEUTRAL) {
						ubidi_setPara(bidi_iter, data + start, end - start, direction, nullptr, &err);
					} else {
						ubidi_setPara(bidi_iter, data + start, end - start, sd->base_para_direction, nullptr, &err);
					}
				} 
			}
			if (U_FAILURE(err)) {
				ubidi_close(bidi_iter);
				bidi_iter = nullptr;
				ERR_PRINT(vformat("BiDi reordering for the paragraph failed: %s", u_errorName(err)));
			}
		} else {
			bidi_iter = nullptr;
			ERR_PRINT(vformat("BiDi iterator allocation for the paragraph failed: %s", u_errorName(err)));
		}
		sd->bidi_iter.push_back(bidi_iter);
		err = U_ZERO_ERROR;