fix(store): refresh gRPC channels after address changes

[bitflicker64]

Purpose of the PR

• close [Bug][HStore][Kubernetes] Data writes remain unavailable after Store pod replacement due to stale DNS resolution #3124

HStore caches gRPC channels and blocking/asynchronous stubs by Store target.
When a stable target resolves to a different address, those pools can retain the
failed transport indefinitely even though the replacement Store is reachable.

This is the channel-lifecycle half of #3124. Complete recovery behind a stable
DNS name still requires the finite positive DNS TTL from #3126; this patch does
not bypass an indefinitely stale JVM DNS cache.

Main Changes

• Fingerprint each target's sorted resolved address set before selecting a
  channel.
• Atomically shut down and replace the channel pool when that fingerprint
  changes or when an initially unresolved target first resolves.
• Rebuild blocking and asynchronous stub pools when their channels no longer
  belong to the current pool.
• Order concurrent resolutions and retry in-flight stub builds so stale work
  cannot replace or return retired channels.
• Add four self-contained refresh regression tests without a running PD or
  Store cluster.

The validated implementation was developed through commits bf9086ee,
4dd41233, 26b333ab, and c71c77a0.

Verifying these changes

• Need tests and can be verified as follows:
  • mvn test -pl hugegraph-store/hg-store-test -am -Dtest=AbstractGrpcClientTest -Dsurefire.failIfNoSpecifiedTests=false: 4 distinct tests passed with 0 failures, errors, or skips on Java 11.
  • mvn test -pl hugegraph-store/hg-store-test -am -P store-client-test -Dsurefire.failIfNoSpecifiedTests=false: the refresh-only client suite ran 4 tests with 0 failures, errors, or skips on Java 11.
  • mvn editorconfig:format: passed with 0 files changed.
  • mvn clean compile -Dmaven.javadoc.skip=true: passed across all 38 reactor modules on Java 11.

Does this PR potentially affect the following parts?

• Dependencies
• Modify configurations
• The public API
• Other affects
• Nope

Documentation Status

• Doc - TODO
• Doc - Done
• Doc - No Need