fix: maintain backward compatibility for remove_reasoning field

aider/models.py

@@ -351,6 +351,7 @@ class Model(ModelSettings):
             self.examples_as_sys_msg = True
             self.use_temperature = False
             self.reasoning_tag = "think"
+            self.remove_reasoning = "think"  # For backward compatibility
             return  # <--
 
         if ("llama3" in model or "llama-3" in model) and "70b" in model:

tests/basic/test_models.py

@@ -285,7 +285,7 @@ class TestModels(unittest.TestCase):
         self.assertTrue(model.use_repo_map)
         self.assertTrue(model.examples_as_sys_msg)
         self.assertFalse(model.use_temperature)
-        self.assertEqual(model.remove_reasoning, "think")
+        self.assertEqual(model.reasoning_tag, "think")
 
         # Test provider/deepseek-v3 case
         model = Model("anotherprovider/deepseek-v3")