### Godot version

4.1.1

### System information

windows 11

### Issue description

When registering a type with class_name and using that class name to declare a variable in code only, autocomplete works as expected anywhere in other nodes/scenes. However, if making a custom scene node that extends a script with the class_name, if that custom scene is instantiated in a different scene, even if the type is specified, it only shows the parent node's functions and not any of the extended functionality. I have made a basic project showing the issue

### Steps to reproduce

I have made a very simple project showing the issue. https://github.com/mmmmmmmmmmmmmmmmmmmdonuts/godot_4_autocomplete_issue essentially, the extended Node scene will only show the custom function when both the type is specified as well as the type afterwards following "as" 
e.g. `@onready var my_class_4: MyClass = $MyClass4 as MyClass`

### Minimal reproduction project

https://github.com/mmmmmmmmmmmmmmmmmmmdonuts/godot_4_autocomplete_issue
static int recursion_depth = 0;
	RecursionCheck recursion(&recursion_depth);
	if (unlikely(recursion.check())) {
		ERR_FAIL_V_MSG(false, "Reached recursion limit while trying to guess type.");
	}
	GDScriptParser::DataType base_type = p_base.type;
	bool is_static = base_type.is_meta_type;
	while (base_type.is_set()) {
		switch (base_type.kind) {
			case GDScriptParser::DataType::CLASS:
				if (base_type.class_type->has_member(p_identifier)) {
					const GDScriptParser::ClassNode::Member &member = base_type.class_type->get_member(p_identifier);
					switch (member.type) {
						case GDScriptParser::ClassNode::Member::CONSTANT:
							r_type.type = member.constant->get_datatype();