[Enhancement]: Decouple Milvus's dependence on vector index types

[foxspy]

Is there an existing issue for this?

• [X] I have searched the existing issues

What would you like to be added?

In Milvus, some code heavily depends on the types of vector indices. This behavior is unreasonable, as Milvus does not grasp the specific differences between different indices. If there are indeed corresponding needs, the index engine (Knowhere) should provide the appropriate interfaces to fulfill them. With the increasing diversity of vector indices, this decoupling needs to be addressed as soon as possible.

Why is this needed?

No response

Anything else?

No response