embedding模型launch_model，会重复加载 v0.11.1.1

[lonrencn]

Describe the bug

embedding模型，用launch_model，即便已经有同名的模型，还是会重新开启，用list_models先查看再处理启动，list的格式非常麻烦，还要做字符串处理，能不能把机制修改一下。同名模型存在，就不反复加载副本了

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Expected behavior

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