Status bar shows wrong model/context when /model used in another session

Description

When running two Claude Code sessions in the same project directory, using /model to switch models in one session causes the status bar in the other session to display the wrong model and context window size.

<img width="1195" height="305" alt="Image" src="https://github.com/user-attachments/assets/37d2ee12-633e-454f-a994-bde71ecb6f99" />
<img width="870" height="277" alt="Image" src="https://github.com/user-attachments/assets/bfc17916-6462-4eba-b789-fef7e4982960" />
<img width="1218" height="280" alt="Image" src="https://github.com/user-attachments/assets/f767c761-b149-41b0-9fff-920453a52fc4" />

Steps to reproduce

1. Open two terminal sessions in the same project directory
2. Session A: Start Claude Code (defaults to Opus 4.6 with 1M context)
3. Session B: Start Claude Code, then run /model sonnet
4. Return to Session A

Expected behavior

Session A's status bar should continue showing Opus 4.6 with 1M context window.

Actual behavior

Session A's status bar changes to show Sonnet 4.6 with 200k context window, even though Session A is still running Opus. The actual model serving responses is still Opus -- only the status bar display is wrong.

In the screenshots below:

• The model responds "Opus." when asked what model it is (correct)
• The status bar shows "Sonnet 4.6 | 151k/200k (75%)" (incorrect -- should be Opus 4.6, ~152k/1M, ~15%)

Screenshots

See attached screenshots showing the discrepancy between the model's self-reported identity and the status bar.

Environment

• Claude Code version: 2.1.81
• OS: macOS (Darwin 25.3.0)
• Shell: zsh