Default model for %%ai magic command

[aleyan]

Problem

I would like to use %%ai cell magic more, but I don't want to type the name of my model each time. Typing 4 characters for "%%ai" plus "b" for a new cell is already more typing than a click for a "new chat" in ChatGPT UI.

Proposed Solution

Make the MODEL_ID positional argument optional. The default value should come from the model configured in the chat interface UI.

Additional Notes

Thank you for this fantastic time saving extension!