ItemLinks: move item links to events, mess up their logic in doing so and lock them behind plando option "item_links" until they're fixed.

Generate.py

@@ -502,6 +502,9 @@ def roll_settings(weights: dict, plando_options: typing.Set[str] = frozenset(("b
             roll_alttp_settings(ret, game_weights, plando_options)
     else:
         raise Exception(f"Unsupported game {ret.game}")
+    # not meant to stay here, intended to be removed when itemlinks are stable
+    if not "item_links" in plando_options:
+        ret.item_links.value = []
     return ret