### Godot version

4.0.2

### System information

Windows 10

### Issue description

EDIT: this was fixed by removing the offending files listed with the MRP and then dragging them back in from my desktop after opening the project~

I was developing my game then suddenly this started happening. I can no longer playtest my game.
I am not 100% sure what caused this but I believe at the time I was making a new inherited scene, saved it, then moved some scenes in the FileSystem tab?

![image](https://user-images.githubusercontent.com/75141902/235264827-62419c7d-963b-4002-9452-a6493a9bfe25.png)


### Steps to reproduce

No idea aaa- x-x

### Minimal reproduction project

Since I have no idea what caused it here's my early project :'D
https://drive.google.com/file/d/14JFZ420AelUNjBIth78msHY29rNjB55_/view?usp=share_link

I was working on these when the error occurred:
- Slot_0.tcsn
- Slot_Clickable.tscn
- Slot_Orphan.tscn
- Slot_Orphan.gd

if (!p_can_assign) {
		push_error("Assignment is not allowed inside an expression.");
		return parse_expression(false); 
	}
	if (p_previous_operand == nullptr) {
		return parse_expression(false); 
	}
#ifdef DEBUG_ENABLED
	VariableNode *source_variable = nullptr;
#endif
	switch (p_previous_operand->type) {
		case Node::IDENTIFIER: {
#ifdef DEBUG_ENABLED