Welcome View: repository picker for background sessions

[DonJayamanne]

No description provided.

[Copilot]

Pull request overview

This PR adds a repository picker for background (CLI) sessions when working in untitled workspaces (i.e., when no workspace folders are open). The changes enable users to select from recently-used repositories or open a new repository via a file picker command.

Changes:

• Added getRecentRepositories() method to IGitService interface to retrieve recently accessed repositories from the Git extension
• Introduced RepositoryAccessDetails interface to represent repository access metadata (root URI and last access time)
• Added commands property to ChatSessionProviderOptionGroup in the VS Code proposed API to support custom commands in option groups
• Implemented repository selection UI for untitled workspaces with last 10 recently-used repositories and an "Open Repository" command

Reviewed changes

Copilot reviewed 9 out of 11 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
src/platform/git/vscode/git.d.ts	Added RepositoryAccessDetails interface, recentRepositories property to API, and removed duplicate readonly kind property
src/platform/git/common/gitService.ts	Added getRecentRepositories() method signature to IGitService interface and reordered imports
src/platform/git/vscode/gitServiceImpl.ts	Implemented getRecentRepositories() method to return recent repositories from Git extension API
src/platform/test/node/simulationWorkspaceServices.ts	Added mock implementation of getRecentRepositories() returning empty array
src/platform/ignore/node/test/mockGitService.ts	Added mock implementation of getRecentRepositories() returning empty array
src/extension/prompt/node/test/repoInfoTelemetry.spec.ts	Added getRecentRepositories mock to test's IGitService mock
src/extension/vscode.proposed.chatSessionsProvider.d.ts	Added optional commands property to ChatSessionProviderOptionGroup
src/extension/chatSessions/vscode-node/copilotCLIChatSessionsContribution.ts	Implemented untitled workspace repository selection logic, added getRepositoryOptionItemsForUntitledWorkspace() method, registered "Open Repository" command, and updated toRepositoryOptionItem() to handle both RepoContext and Uri types
src/extension/chatSessions/vscode-node/chatSessions.ts	Passed contentProvider to registerCLIChatCommands() for command registration
package.json	Registered github.copilot.cli.sessions.openRepository command with menu contribution
package.nls.json	Added localization string for "Open Repository" command