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>
issue: #33285
- implement producing and consuming server of message
- implement management operation for streaming node server
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Signed-off-by: chyezh <chyezh@outlook.com>