### 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)
return u_gep_chr, UCHAR_JOINING_GROUP) == U_JG_REH;
}
_FORCE_INLINE_ bool is_seen_sad(char32_t p_chr) {
	return (u_gep_chr, UCHAR_JOINING_GROUP) == U_JG_SAD) || (u_gep_chr, UCHAR_JOINING_GROUP) == U_JG_SEEN);
}
_FORCE_INLINE_ bool is_tah(char32_t p_chr) {
	return u_gep_chr, UCHAR_JOINING_GROUP) == U_JG_TAH;
}
_FORCE_INLINE_ bool is_teh_marbuta(char32_t p_chr) {
	return u_gep_chr, UCHAR_JOINING_GROUP) == U_JG_TEH_MARBUTA;
}
_FORCE_INLINE_ bool is_yeh(char32_t p_chr) {
	int32_t prop = u_gep_chr, UCHAR_JOINING_GROUP);
	return (prop == U_JG_YEH) || (prop == U_JG_FARSI_YEH) || (prop == U_JG_YEH_BARREE) || (prop == U_JG_BURUSHASKI_YEH_BARREE) || (prop == U_JG_YEH_WITH_TAIL);
}
_FORCE_INLINE_ bool is_waw(char32_t p_chr) {
	return u_gep_chr, UCHAR_JOINING_GROUP) == U_JG_WAW;
}
_FORCE_INLINE_ bool is_transparent(char32_t p_chr) {
	return u_gep_chr, UCHAR_JOINING_TYPE) == U_JT_TRANSPARENT;
}
_FORCE_INLINE_ bool is_ligature(char32_t p_chr, char32_t p_nchr) {
	return (is_lam(p_chr) && is_alef(p_nchr));
}
_FORCE_INLINE_ bool is_connected_to_prev(char32_t p_chr, char32_t p_pchr) {
	int32_t prop = u_gep_pchr, UCHAR_JOINING_TYPE);
	return (prop != U_JT_RIGHT_JOINING) && (prop != U_JT_NON_JOINING) ? !is_ligature(p_pchr, p_chr) : false;
}
bool TextServerAdvanced::icu_data_loaded = false;
bool TextServerAdvanced::_has_feature(Feature p_feature) const {