issue: #43897
- Part of collection/index related DDL is implemented by WAL-based DDL
framework now.
- Support following message type in wal, CreateCollection,
DropCollection, CreatePartition, DropPartition, CreateIndex, AlterIndex,
DropIndex.
- Part of collection/index related DDL can be synced by new CDC now.
- Refactor some UT for collection/index DDL.
- Add Tombstone scheduler to manage the tombstone GC for collection or
partition meta.
- Move the vchannel allocation into streaming pchannel manager.
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Signed-off-by: chyezh <chyezh@outlook.com>
issue: #40638
- Add `ChannelID` for streaming replica in future.
- Remove the pchannel count fair balance policy for streaming.
- Add Score based vchannel fair balance policy for streaming.
- Add pchannel stats manager to collect the stats of pchannel for
balancer.
- Add configuration and metrics for new balance policy
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Signed-off-by: chyezh <chyezh@outlook.com>