issue: #37718
This PR refine the shard client ref counter, dec ref counter won't
release client anymore, and only permit shard client manager to remove
client.
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Signed-off-by: Wei Liu <wei.liu@zilliz.com>
issue: #37115
the old implementation update shard cache and shard client manager at
same time, which causes lots of conor case due to concurrent issue
without lock.
This PR decouple shard client manager from shard cache, so only shard
cache will be updated if delegator changes. and make sure shard client
manager will always return the right client, and create a new client if
not exist. in case of client leak, shard client manager will purge
client in async for every 10 minutes.
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Signed-off-by: Wei Liu <wei.liu@zilliz.com>
