issue: ##36621
- For simple types in a struct, add "string" to the JSON tag for
automatic string conversion during JSON encoding.
- For complex types in a struct, replace "int64" with "string."
Signed-off-by: jaime <yun.zhang@zilliz.com>
1. Move the common modules of streamingNode and dataNode to flushcommon
2. Add new GetVChannels interface for rootcoord
issue: https://github.com/milvus-io/milvus/issues/33285
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Signed-off-by: bigsheeper <yihao.dai@zilliz.com>