Fleet command multi clone

### Describe the feature or problem you'd like to solve

In order to not squash file changes, clone repo to multiple directories and have git as the communication mechanism

### Proposed solution

Allow /fleet to clone the repository multiple times and rely on git functions to handle file conflicts and file squash incidents.

### Example prompts or workflows

_No response_

### Additional context

_No response_

首先跟踪 /fleet 命令及其现有的仓库克隆工作流。确定多个克隆目录和基于 git 的通信应如何融入当前行为；当 /fleet 能够管理多个克隆，同时不会 squash 文件更改或让冲突变得含糊不清时，这项工作就完成了。

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