issue: #43897
- add ddl messages proto and add some message utilities.
- support shard/exclusive resource-key-lock.
- add all ddl callbacks future into broadcast registry.
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Signed-off-by: chyezh <chyezh@outlook.com>
issue: #42416
- Rename the InsertMetric into ModifiedMetric.
- Add L0 control configuration.
- Add some L0 current state collect.
Signed-off-by: chyezh <chyezh@outlook.com>
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>