[Fix] Deduplicate model lists and remove dead assignment

Adds dedup to get_key_models and get_team_models to prevent duplicate
entries when access group member models overlap with proxy_model_list.
Removes dead assignment of all_models in get_team_models.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

litellm/proxy/auth/model_checks.py

@@ -122,6 +122,9 @@ def get_key_models(
         include_model_access_groups=include_model_access_groups,
     )
 
+    # deduplicate while preserving order
+    all_models = list(dict.fromkeys(all_models))
+
     verbose_proxy_logger.debug("ALL KEY MODELS - {}".format(len(all_models)))
     return all_models
 
@@ -148,14 +151,15 @@ def get_team_models(
             if include_model_access_groups:
                 all_models_set.update(model_access_groups.keys())
 
-    all_models = list(all_models_set)
-
     all_models = _get_models_from_access_groups(
         model_access_groups=model_access_groups,
         all_models=list(all_models_set),
         include_model_access_groups=include_model_access_groups,
     )
 
+    # deduplicate while preserving order
+    all_models = list(dict.fromkeys(all_models))
+
     verbose_proxy_logger.debug("ALL TEAM MODELS - {}".format(len(all_models)))
     return all_models
 

tests/test_litellm/proxy/auth/test_model_checks.py

@@ -43,6 +43,7 @@ def test_get_team_models_all_proxy_models_includes_access_groups():
     assert "group-b" in result
     assert "model1" in result
     assert "model2" in result
+    assert len(result) == len(set(result)), "result should have no duplicates"
 
 
 def test_get_team_models_all_proxy_models_without_include_flag():
@@ -94,6 +95,7 @@ def test_get_key_models_all_proxy_models_includes_access_groups():
     assert "group-a" in result
     assert "model1" in result
     assert "model2" in result
+    assert len(result) == len(set(result)), "result should have no duplicates"
 
 
 def test_get_key_models_passes_include_model_access_groups():