[Bug] Performance degradation in Claude Code over past three days

**Bug Description**
Fable performance feels degraded in the past three days.

Might be a me/implementation issue. But putting this feedback here anyway with access to the 7 days conversations just in case it's not

**Environment Info**
- Platform: linux
- Terminal: tmux
- Version: 2.1.268
- Feedback ID: d23a4dad-85f5-48b7-b1d6-df8e166e5bdf

**Errors**
```json
[]
```

Start with the provided Feedback ID d23a4dad-85f5-48b7-b1d6-df8e166e5bdf and review the available seven-day conversations. Reproduce the reported degradation on Linux in tmux with version 2.1.268, then compare behavior against the recent baseline. Done means identifying a reproducible regression or documenting why the performance change cannot be reproduced.

索引モデルが issue の本文から書いたものです。