Renaming branchs is painful.

Renaming branchs is painful. First of all, I can't change the default branch prefix to use a prefix that includes the issue number.
I create a worktree with the correct branch name but then the branch is renamed (why?!). Then you don't allow me to rename it again: "... tool only permits one rename per session and the branch ..."

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| Field | Value |
| --- | --- |
| App version | 1.0.25 |
| OS | macOS 15.7.2 |
| Theme | GitHub |
| Path | /chat |
| Tenure | Week 6 |

Start with the /chat flow and reproduce the reported behavior using the app version and macOS details provided. Check how default branch prefixes, worktree-created branches, and the one-rename-per-session restriction interact. Done means the requested issue-number prefix and intended branch renaming flow work without the reported restriction.

索引モデルが issue の本文から書いたものです。