[General] Cleanup "stale" closed PR red icon?

**Mood:** 😊
**Category:** General

Cleanup "stale" closed PR red icon? In one session, I ahd completed and merged a PR (well copilot actually did which I found inappropriate and wound-up deleting the PR). After this, I continued the session to further refine the work. But the icon for the session in the left view remained as the Red deleted icon for the full duration because the PR was linked as "closed" from then-on.

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| Field | Value |
| --- | --- |
| App version | 0.2.34 |
| OS | Windows 10.0.26200 |
| Theme | GitHub |
| Path | /chat |
| Tenure | Week 2 |

首先，使用报告中的应用版本以及一个已合并或已删除的 pull request，在 /chat 上复现会话状态。跟踪左侧视图中的会话图标如何反映所关联 pull request 的状态；当会话继续或 pull request 状态发生变化后，该图标不再一直显示为红色的已删除指示器时，即表示完成。

由索引模型根据 Issue 内容生成。