/restart command always fails - cannot find sessions

## Bug Report

### Description
The \/restart\ command consistently fails. It always errors out trying to match a session ID that cannot be found.

### Error Message

Error: No session, task, or name matched '2d7508a4-4194-4c6b-9608-dc1f05098128'.

To resume by session or task ID: copilot --resume=
To resume by name: copilot --resume=
To name a new session: copilot --name=
To pick from existing sessions: copilot --resume
To start a new session with ID: copilot --session-id=

[process exited with code 1 (0x00000001)]

### Steps to Reproduce
1. Run a Copilot session
2. Use the \/restart\ command
3. Command always fails with exit code 1

### Expected Behavior
The \/restart\ command should successfully restart the session.

### Actual Behavior
The command always exits with code 1, unable to find the session.

Start by reproducing the failure from a running Copilot session with the /restart command, then trace how the command looks up the current session ID. Done means /restart successfully starts the session without the “No session, task, or name matched” error and exits successfully.

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