Feature request: Attach an existing chat or session to a Project

Start by reviewing the documented ghapp://session/new deep link and the app's existing Project and session behavior. The issue does not name source files or tests; done would require a defined, supported way to associate an existing conversation with an existing or new Project while preserving its transcript and context.

Describe the feature or problem you'd like to solve

The GitHub Copilot app treats general chats and Project sessions separately. After a conversation starts outside a Project, there is no supported way to associate it with a Project later. The user must start a new session, leaving the original conversation and its context behind.

Proposed solution

Allow an existing chat or session to be attached or moved to an existing or newly created Project while preserving its transcript and context.

This could be available through:

• A Move to Project action in the app.
• An agent or extension tool for attaching the current session to a Project.
• An option to attach the current session when creating a Project.
• A deep link that starts a session for a specific Project, including a local-folder Project.

Example prompts or workflows

1. Begin researching an idea in a general chat, then continue the same conversation in the relevant Project.
2. Create or open a Project after a conversation has started and attach the current session to it.
3. Let an automated workflow create a Project and associate the current session with it.
4. Organize an existing chat under a Project without restarting the conversation.

Additional context

The documented ghapp://session/new deep link accepts a GitHub repository, branch, pull request, prompt, and mode, but not a local path or Project ID. The app can add a local folder as a Project, but no documented UI, deep link, or agent tool associates the current conversation with it.

Observed on GitHub Copilot app 1.1.22 on macOS.