issue: #43897
- Return LastConfirmedMessageID when wal append operation.
- Add resource-key-based locker for broadcast-ack operation to protect
the coord state when executing ddl.
- Resource-key-based locker is held until the broadcast operation is
acked.
- ResourceKey support shared and exclusive lock.
- Add FastAck execute ack right away after the broadcast done to speed
up ddl.
- Ack callback will support broadcast message result now.
- Add tombstone for broadcaster to avoid to repeatedly commit DDL and
ABA issue.
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Signed-off-by: chyezh <chyezh@outlook.com>
issue: #38399
- Make a timetick-commit-based write ahead buffer at write side.
- Add a switchable scanner at read side to transfer the state between
catchup and tailing read
Signed-off-by: chyezh <chyezh@outlook.com>
