Add note/comment to session, so I can add a thought to the session without se...

Add note/comment to session, so I can add a thought to the session without sending off an agent. Instead, I can come back to my session when I am ready and see the note/comment I left.

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| Field | Value |
| --- | --- |
| App version | 1.0.18 |
| OS | Windows 10.0.26200 |
| Theme | Xotopio |
| Path | /chat |
| Tenure | Week 5 |

Start at the /chat path and trace how sessions are displayed and persisted. Define the note interaction and storage from the existing session flow; it is done when a user can save a thought without sending an agent and see it again when returning to the session.

索引モデルが issue の本文から書いたものです。