Support ModelName Settings

[wangyumu]

User can config the Model Name in Settings to test GPT4-o or other new models like below:

and the default value keep the same as before.

for #90

[vercel]

@wangyumu is attempting to deploy a commit to the HaiTao Wu's projects Team on Vercel.

A member of the Team first needs to authorize it.

[oleteacher]

This would be wonderful addition, using this in classroom and ability to switch models needed bad. Where can this mod be found?

Thank you!