### Godot version

8449592d92eaeef990f5502b419d491ee3eeb7a6

### System information

Windows 11

### Issue description

Zooming in the script editor on an empty script freezes the entire editor for a few seconds, but if the file is large then it freezes for 4-5 seconds (which is unacceptable). Looks like a recent regression.

### Steps to reproduce

Just zoom in/out on the large script file.

### Minimal reproduction project

N/A
const ShapedTextDataFallback *sd = shaped_owner.get_or_null(p_shaped);
	ERR_FAIL_COND_V(!sd, 0.0);
	MutexLock lock(sd->mutex);
	if (!sd->valid) {
		const_cast<TextServerFallback *>(this)->_shaped_text_shape(p_shaped);
	}
	return sd->descent + sd->extra_spacing[SPACING_BOTTOM];
}
double TextServerFallback::_shaped_text_get_width(const RID &p_shaped) const {
	const ShapedTextDataFallback *sd = shaped_owner.get_or_null(p_shaped);
	ERR_FAIL_COND_V(!sd, 0.0);
	MutexLock lock(sd->mutex);
	if (!sd->valid) {
		const_cast<TextServerFallback *>(this)->_shaped_text_shape(p_shaped);
	}
	return Math::ceil(sd->width);
}
double TextServerFallback::_shaped_text_get_underline_position(const RID &p_shaped) const {
	const ShapedTextDataFallback *sd = shaped_owner.get_or_null(p_shaped);
	ERR_FAIL_COND_V(!sd, 0.0);
	MutexLock lock(sd->mutex);
	if (!sd->valid) {
		const_cast<TextServerFallback *>(this)->_shaped_text_shape(p_shaped);
	}
	return sd->upos;
}
double TextServerFallback::_shaped_text_get_underline_thickness(const RID &p_shaped) const {