Merge pull request #1590 from hypn4/main

feat: add `extra_body`field and use in model settings.

aider/coders/base_coder.py

@@ -1399,6 +1399,7 @@ class Coder:
                 self.stream,
                 temp,
                 extra_headers=model.extra_headers,
+                extra_body=model.extra_body,
                 max_tokens=model.max_tokens,
             )
             self.chat_completion_call_hashes.append(hash_object.hexdigest())