issue: #43897
- Alter collection/database is implemented by WAL-based DDL framework
now.
- Support AlterCollection/AlterDatabase in wal now.
- Alter operation can be synced by new CDC now.
- Refactor some UT for alter DDL.
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Signed-off-by: chyezh <chyezh@outlook.com>
Read metadata such as segments, binlogs, and partitions concurrently at
the collection level.
issue: https://github.com/milvus-io/milvus/issues/37630
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Signed-off-by: bigsheeper <yihao.dai@zilliz.com>