issue: #38399
related PR: #39522
- Just implement exclusive broadcaster between broadcast message with
same resource key to keep same order in different wal.
- After simplify the broadcast model, original watch-based broadcast is
too complicated and redundant, remove it.
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Signed-off-by: chyezh <chyezh@outlook.com>
issue: #38399
- broadcast message can carry multi resource key now.
- implement event-based notification for broadcast messages
- broadcast message use broadcast id as a unique identifier in message
- broadcasted message on vchannels keep the broadcasted vchannel now.
- broadcasted message and broadcast message have a common broadcast
header now.
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Signed-off-by: chyezh <chyezh@outlook.com>
