Make indirectly inherited EditorScripts appear in the command palette

[sockeye-d]

I added a new ScriptServer::get_indirect_inheriters_list function that recursively walks the inheritance tree from ScriptServer::get_inheriters_list. From the MRP of the attached issue, both EditorScripts show up now:

I think it's possible to rewrite it without the second List allocation like this:

size_t classes_start_size = r_classes->size();
get_inheriters_list(p_base_type, r_classes);
size_t classes_end_size = r_classes->size();
for (int i = classes_start_size; i < classes_end_size; i++) {
	const StringName &inheritor = r_classes[i];
	r_classes->push_back(inheritor);
	get_indirect_inheriters_list(inheritor, r_classes);
}

but I'm not sure if that'd work in all cases and it's more complicated.

Fixes #113749