Sessions dies after cancelling a response

After cancelling a response, or maybe after having a message queued and then cancelling the current response and the one from the queued message, the session stops responding. It just thinks forever with no output. Eventually a popup comes up suggesting to restart the session, but that doesn't work either. The only thing that works is quitting the app and reopening it, which takes clicking on it about 5 times and waiting 5 minutes. Also, in similar cases sometimes, messages get lost, and they show in the chat window, but the agent has no record of them.

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| Field | Value |
| --- | --- |
| App version | 1.0.23 |
| OS | Windows 10.0.26310 |
| Theme | Noir Essence |
| Path | /chat |
| Tenure | Week 4 |

Start at the /chat entry point and reproduce the failure on Windows 10 after cancelling the current response and any queued response. Check the session's behavior when it remains stuck thinking, when restart is attempted, and when messages appear in the chat without reaching the agent; done means the session responds normally and queued messages are not lost.

Written by the indexing model from the issue text.