refactor(provider): use default model for code improvement prompt

etc/tool/improve_code.py

@@ -30,7 +30,7 @@ Don't remove license comments.
 print("Create code...")
 response = []
 for chunk in g4f.ChatCompletion.create(
-    model=g4f.models.gpt_35_long,
+    model=g4f.models.default,
     messages=[{"role": "user", "content": prompt}],
     timeout=300,
     stream=True
@@ -42,4 +42,4 @@ response = "".join(response)
 
 if code := read_code(response):
     with open(path, "w") as file:
-        file.write(code)
+        file.write(code)