【SCU】【PPMix No.37】Qwen2vl 代码解析+使用流程

[yangrongxinuser]

1. 完成 Qwen2-VL 多模态模型的详细代码解析 2. 编写完整的环境配置 3. 提供模型训练与推理的示例代码
   @luyao-cv

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[luyao-cv]

修改内容：

1. 在开头处总结这篇文章的内容。
2. 阅读下文章，理解分阶段训练。
3. 图片预处理这部分可以再详细点，如何切片处理。
4. 前向过程可以添加理解下。