Plan mode constantly cannot update plans with revisions.

Plan mode constantly cannot update plans with revisions. Troubleshooting in the session appears to indicate that the file is being cached and not re-read when the agent updates it on disk; my agent had to actually delete and recreate the plan file to get the view in the canvas to update.

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| Field | Value |
| --- | --- |
| App version | 1.1.6 |
| OS | Ubuntu 24.4.0 |
| Theme | ABOLKOG |
| Path | /chat |
| Tenure | Week 13 |

Start at the /chat path in app version 1.1.6 and reproduce a plan revision in Plan mode on Ubuntu 24.4.0, observing whether the canvas rereads the changed plan file. Done means revisions appear in the canvas without deleting and recreating the plan file.

索引モデルが issue の本文から書いたものです。