Add support for plan exit mode in Copilot CLI configuration and handling

[DonJayamanne]

No description provided.

[Copilot]

Pull request overview

Adds a new configuration flag to gate Copilot CLI “plan exit mode” handling, and wires that flag through CopilotCLISession plus related unit tests.

Changes:

• Introduces chat.cli.planExitMode.enabled configuration key and surfaces it in package.json/package.nls.json.
• Updates CopilotCLISession to conditionally attach the exit_plan_mode.requested event handler based on the new setting.
• Updates/extends Copilot CLI session-related tests to pass IConfigurationService and validate the disabled behavior.

Reviewed changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
src/platform/configuration/common/configurationService.ts	Adds a new config key for plan exit mode enablement.
src/extension/chatSessions/copilotcli/node/copilotcliSession.ts	Gates exit_plan_mode.requested handler registration behind the new config.
src/extension/chatSessions/copilotcli/node/test/copilotcliSession.spec.ts	Injects config service into session creation and adds a test for the disabled path.
src/extension/chatSessions/copilotcli/node/test/copilotCliSessionService.spec.ts	Updates session construction in tests to provide IConfigurationService.
src/extension/chatSessions/vscode-node/test/copilotCLIChatSessionParticipant.spec.ts	Updates test session construction to provide IConfigurationService.
package.json / package.nls.json	Adds the new contributed setting and its localized description.