Add GitHub Copilot integration

[hideyukikodama]

Summary

This pull request adds native GitHub Copilot integration to jupyter-ai. More background and implementation details could be found in #1310.

Demo

Here is a screen capture video demonstrating how it works: Movie link

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This is an initial proof of concept, and I'm very open to your feedback, improvements, or suggestions on how to better align this with the goals!

[dlqqq]

@hideyukikodama Thank you for this contribution, and welcome to Jupyter AI! GitHub Copilot support has been highly requested by some users. It is great to see others contributing to this effort. 🤗

I've left some feedback below. The code looks very clean! ❤️

The only greater concern I have is with the /github slash command. We generally avoid adding provider-specific features in Jupyter AI. This helps keep Jupyter AI maintainable & vendor-neutral. Can you help document the authentication flow in this PR? In a future review, we can use that design to explore ways that this PR can support authentication without adding a /github command.

If adding a /github command turns out to be the only way to do this, we may provide this through a separate jupyter-ai-copilot package. We are open to the idea of adding model-specific packages, as long as they aren't required by jupyter-ai itself.

[dlqqq]

Setting the list of model IDs to ["*"] has a special meaning in Jupyter AI. This denotes a registry provider, i.e. a provider where the user has to type out the model ID. Since there's only one model served by this provider, it would be better to make this explicit:

Suggested change

	class GitHubCopilotProvider(BaseProvider):
	id = "github-copilot"
	name = "GitHub Copilot"
	models = ["*"]
	model_id_key = "model"
	pypi_package_deps = ["pylspclient"]
	help = (
	"Make sure you've installed copilot-language-server [https://www.npmjs.com/package/@github/copilot-language-server](https://www.npmjs.com/package/@github/copilot-language-server) . "
	"Set this absolute path to `lsp_bin_path`."
	)
	class GitHubCopilotProvider(BaseProvider):
	id = "github"
	name = "GitHub"
	models = ["Copilot"]
	model_id_key = "model"
	pypi_package_deps = ["pylspclient"]
	help = (
	"Make sure you've installed copilot-language-server [https://www.npmjs.com/package/@github/copilot-language-server](https://www.npmjs.com/package/@github/copilot-language-server) . "
	"Set this absolute path to `lsp_bin_path`."
	)

[dlqqq]

The BaseProvider class allows developers to override the default definition of these 2 methods, which list the available chat & completion models:

    @classmethod
    def chat_models(self):
        """Models which are suitable for chat."""
        return self.models

    @classmethod
    def completion_models(self):
        """Models which are suitable for completions."""
        return self.models

I recommend overriding these methods to have the github:copilot model only show in the list of completion models, and be hidden from the list of chat models:

Suggested change

	def __init__(
	self,
	**kwargs,
	):
	super().__init__(**kwargs)
	self._llm = GitHubCopilotLLM(lsp_bin_path=self.lsp_bin_path)
	def __init__(
	self,
	**kwargs,
	):
	super().__init__(**kwargs)
	self._llm = GitHubCopilotLLM(lsp_bin_path=self.lsp_bin_path)
	@classmethod
	def chat_models(self):
	"""Models which are suitable for chat."""
	return []
	@classmethod
	def completion_models(self):
	"""Models which are suitable for completions."""
	return ["copilot"]

[dlqqq]

How does the user sign in if this method doesn't provide any environment variables / passwords? Does the Copilot LSP server open a new browser for a user to log in automatically?