fix jina adding issure and term weight refinement (#974)

### What problem does this PR solve?

#724 #162

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)
- [x] New Feature (non-breaking change which adds functionality)

rag/llm/__init__.py

@@ -28,6 +28,7 @@ EmbeddingModel = {
     "FastEmbed": FastEmbed,
     "Youdao": YoudaoEmbed,
     "BaiChuan": BaiChuanEmbed,
+    "Jina": JinaEmbed,
     "BAAI": DefaultEmbedding
 }