Use new commits instead ammend+force push

### Feature summary

As title suggests

### What problem are you trying to solve?

Please make the agent prefer creating new commits instead of amending+force pushing changes. I noticed that when I ask the agent to remove some code, it consistently remove the code, amend the current commit and force push to the remote repo without additional user consent. Force push is a destructive operation that shouldn't be easily executed like this.

Here is an example of what happened. There is no user interaction between when I submitted the prompt in the screenshot and when the agent force push the amended commit.

### Proposed solution

Make the agent create a new commit instead, or require user consent for executing force push.

### Workflow impact

_No response_

### Installation context

_No response_

### Additional context

_No response_

Issue ではファイルもテストも指定されていません。まず、agent の commit amendment と force-push の workflow を追跡してください。完了の条件は、agent がデフォルトで新しい commit を作成するか、force-push の前にユーザーへ明示的な同意を求めることです。

索引モデルが issue の本文から書いたものです。