issue: #41544
- simplify the proto message for flush and create segment.
- simplify the msg handler for flowgraph.
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Signed-off-by: chyezh <chyezh@outlook.com>
issue: #33285
- move most cgo opeartions related to search/query into segcore package
for reusing for streamingnode.
- add go unittest for segcore operations.
Signed-off-by: chyezh <chyezh@outlook.com>