The model picker should show the provider (e.

The model picker should show the provider (e.g. create sections per provider). currently it's impossible to see which model/entry is from which provider especially if multiple provider have the same model.

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| Field | Value |
| --- | --- |
| App version | 1.1.7 |
| OS | Windows 10.0.26200 |
| Theme | GitHub |
| Path | /chat |
| Tenure | Week 6 |

从桌面应用的 /chat 视图中的模型选择器开始，追踪 provider 和 model 条目是如何组装的。当选择器能够按 provider 对条目进行可见的分组或标注（包括不同 provider 提供相同模型名称的情况）时，这项工作就完成了。

由索引模型根据 Issue 内容生成。