Be able to create, see and use App level Canvas.

Be able to create, see and use App level Canvas.
A dedicated area in the GHCP App where my User/Global Canvas are immedialy accesible without the need of individual Repos

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| Field | Value |
| --- | --- |
| App version | 1.1.6 |
| OS | Windows 10.0.26200 |
| Theme | GitHub |
| Path | /chat |
| Tenure | Week 4 |

从 GitHub Copilot 应用的 /chat 路径开始，检查 User/Global Canvas 当前如何依赖单个仓库。定义专用的应用级区域，使用户无需打开仓库即可创建、查看和使用这些 Canvas；完成的标准是这三项操作都可从应用区域使用。

由索引模型根据 Issue 内容生成。