Optional Proprietary AI support

[trymeouteh]

An option to use proprietary AI models like chatGPT in Privy.

The AI models will not run on the local machine, but will require you to enter API keys to use these models.

When using these models, Privy will send the calls to the API and the API will return the output.

And all of these proprietary models should be listed in Privy as proprietary and require internet connection to inform the users that they are not private and offline.

Or an alternative to this is to ensure the Privy extension does not conflict with the Rubberduck extension when both are installed and used
#33

This is also a feature request for Rubberduck, the project Privy is a fork of
rubberduck-ai/rubberduck-vscode#122