feat: 支持视频上传功能，就像上传图片一样

[vdjango]

Check Existing Issues

• I have searched for all existing open AND closed issues and discussions for similar requests. I have found none that is comparable to my request.

Verify Feature Scope

• I have read through and understood the scope definition for feature requests in the Issues section. I believe my feature request meets the definition and belongs in the Issues section instead of the Discussions.

Problem Description

部分大模型支持视频理解，但是我发现只支持图片，上传视频并不支持。我查看了源代码，只有图片的处理逻辑。当然我不确定是否有外部方法已经支持，但我觉得可以添加到内部，就像上传图片一样，后端、前端的逻辑和图片一样

Desired Solution you'd like

像图片一样可以上传，可以聊天（上传视频）

Alternatives Considered

我大概率自己二次开发了，应该很快支持了。看看你们这边要不要添加上去，我改的可能不太合适上传，我直接拉main分支弄的

Additional Context

No response