LLamaLLM 加载器

cli_demo.py、api.py: 兼容loader加载器

loader.py: 模型重载
定义 generatorAnswer 增加 AnswerResultStream
   定义generate_with_callback收集器，在每次响应时将队列数据同步到AnswerResult
requirements.txt 变更项目依赖

bug fixed & ui Moidfy

2: add backgound image

* 1: 基于langchain的bing search agent添加bing搜索支持(百度不靠谱,Google不可用)
2: 调整输入框交互模式,对话/知识库/搜索,三选一

* fixed bug of message have no text

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Co-authored-by: root <jv.liu@i1368.com>

add Knowledge Base delete and file delete