I'd like to be able to select with my mouse selected text in the prompt outpu...

I'd like to be able to select with my mouse selected text in the prompt outputs vs having the copy the entire prompt using the copy icon at the bottom left of the prompt.

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| Field | Value |
| --- | --- |
| App version | 1.1.0 |
| OS | Ubuntu 24.4.0 |
| Theme | GitHub |
| Path | /chat |
| Tenure | Day 2 (Week 1) |

从 /chat 路径开始，检查 prompt 输出区域及其当前的复制图标行为。保留现有的复制操作，同时让 prompt 输出中的单独文本可以使用鼠标选择，然后验证可以复制选中的文本，而不会复制整个 prompt。

由索引模型根据 Issue 内容生成。