Need a way to cancel/manage messages in the queue.

Need a way to cancel/manage messages in the queue. (It should be as easy as in the cli)

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| Field | Value |
| --- | --- |
| App version | 1.1.8 |
| OS | Windows 10.0.26200 |
| Theme | GitHub |
| Path | /chat |
| Tenure | Week 2 |

Start in the desktop app's /chat experience and compare how message cancellation or management works in the CLI. Clarify which queue actions are needed and how they should behave for users. Done means the agreed queue-management actions are available in the chat experience and can be verified on Windows 10.

索引モデルが issue の本文から書いたものです。