Forking a session doesn't provide any visual indication of ongoing progress o...

Forking a session doesn't provide any visual indication of ongoing progress or asynchronous execution (other than printing the "forking session" message). There is also no noticiation when the forking is finished.

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| Field | Value |
| --- | --- |
| App version | 1.0.22 |
| OS | Windows 10.0.26200 |
| Theme | GitHub |
| Path | /chat |
| Tenure | Week 18 |

Start by reproducing the session fork flow on the /chat path using app version 1.0.22 and observe the current "forking session" message. Identify where the fork begins and finishes, then define done as a visible indication during asynchronous execution and a notification when forking completes.

Written by the indexing model from the issue text.