User-level configured model is not used in new sessions #4434

Describe the bug

When setting a user-default model via "/config model" it is not used when creating a new session via "/clear" or via the sessions interface. Only when exiting and restarting the CLI client is the user-default model being used.

Affected version

No response

Steps to reproduce the behavior

1. /config model (set a model e.g. Sonnet 5)
2. /model (set a session model e.g. GPT-5.6 Luna)
3. /clear or /new (used model for the session is still GPT-5.6 Luna NOT Sonnet 5)

Expected behavior

When creating a new session the user-default model should be used

Additional context

• GitHub Copilot CLI 1.0.79
• macOS