Add Github Copilot-like code completion/suggestion functionality

[michaelchia]

Problem

• Is there any future plans for adding a code completion/suggestion type functionality in this extension?
• Something similar to a github copilot or starcoder's jupytercoder chrome extension (https://github.com/bigcode-project/jupytercoder)
• Would be ideal if able to show code suggestions before accepting them as per those existing tools.
  • But if the jupyter UI is unable to do that natively, just having a hot key to trigger the autocomplete without showing the suggestion would be fine as well.
• Would prefer something that isn't magic based as it would be troublesome to attach the magic in every cell.

Proposed Solution

• On the server side, may require defining new providers for LLMs that output code given code prefix and optional suffix (for fill in the blank).
• E.g. huggingface starcoder and google's code-gecko.
• Maybe be able to use general LLMs by providing a prompt template that returns code.

Additional context

• I am using jupyter in a corporate setting where I am unable to install chrome extensions (starcoder's jupyter plugin) or vscode (github copilot).

[JasonWeill]

Currently, Jupyter AI is designed such that it only sends a query to a language model when the user explicitly requests to do so. Autocompletion and automatic code suggestion would change that design principle, so we might have to think about the best ways to make users opt in to share their code with a language model to make this work. Thank you for your suggestion!

[JasonWeill]

Related automated functionality issue: #290

[krassowski]

Related JupyterLab issue: Integrate github copilot with jupyterlab #14267.

[krassowski]

Just highlighting that a pull request to core JupyterLab adding inline completer that could enable this feature is ready for review: jupyterlab/jupyterlab#15160.

[JasonWeill]

jupyterlab/jupyterlab#15160 is now merged into JupyterLab, so this issue may be redundant.

[krassowski]

I believe this can be closed. #465 implemented this, but did not auto-close this issue because it was initially merged into a non-main branch.