Terminal color scheme should be more friendly.

Terminal color scheme should be more friendly. When using Claude Code with the default one, it's hard to examine the code outside the diff blocks carefully.

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| Field | Value |
| --- | --- |
| App version | 1.1.2 |
| OS | Windows 10.0.26200 |
| Theme | GitHub |
| Path | /chat |
| Tenure | Day 3 (Week 1) |

Start by reproducing the /chat terminal view on Windows 10.0.26200 with the GitHub theme and inspect how code outside diff blocks is displayed; done means the terminal color scheme makes that code easy to examine while preserving readable diff blocks.

索引モデルが issue の本文から書いたものです。