add separate can_exclude property, so non-progression items can be marked non-excluded

BaseClasses.py

@@ -1104,6 +1104,7 @@ class Item():
     world: Optional[MultiWorld] = None
     game: str = "Generic"
     type: str = None
+    can_be_excluded: bool = True  # change manually if you want some non-advancement item to not be excluded
     pedestal_credit_text: str = "and the Unknown Item"
     sickkid_credit_text: Optional[str] = None
     magicshop_credit_text: Optional[str] = None
@@ -1117,6 +1118,8 @@ class Item():
         self.player = player
         self.code = code
 
+        self.can_be_excluded = not advancement
+
     @property
     def hint_text(self):
         return getattr(self, "_hint_text", self.name.replace("_", " ").replace("-", " "))
@@ -1136,6 +1139,10 @@ class Item():
     def __hash__(self):
         return hash((self.name, self.player))
 
+    @property
+    def can_exclude(self) -> bool: 
+        return not (self.advancement or self.smallkey or self.bigkey) and self.can_be_excluded
+
     @property
     def crystal(self) -> bool:
         return self.type == 'Crystal'