[FEATURE] A way to switch models mid-session that does not persist to the settings

Preflight Checklist

• [x] I have searched existing requests and this feature hasn't been requested yet
• [x] This is a single feature request (not multiple features)

Problem Statement

Sometimes I want to switch between Sonnet or Opus mid-session using the /model command, but I almost never want this change to persist across sessions.

Proposed Solution

One of these two options:

• Something in the model picker that can be checked/unchecked to control persisting the change to the config file
• A separate slash command that opens the model picker but does not persist the choice

Alternative Solutions

Exit the session, restart it with claude -c -m sonnet but this is unwieldy. Sometimes I just start a new session entirely.

Priority

Medium - Would be very helpful

Feature Category

Interactive mode (TUI)

Use Case Example

Implement a plan with Opus. Look and see it needs some cleanup. I want to switch to Sonnet to perform that cleanup.

Additional Context

_No response_