PHOENIX-7769 Initialize and Close replication log groups as part of RS startup and shutdown

[tkhurana]

Summary

• Eagerly initialize ReplicationLogGroup instances during RS startup (prewarm phase) when synchronous replication is enabled, so they are ready before the first mutation arrives.
• Close all ReplicationLogGroup instances belonging to a server during RS shutdown via a new ReplicationLogGroup.closeAll(serverName) method.
• Extract serverName capture from the test subclass into the parent PhoenixRegionServerEndpoint, removing redundant code.
• Fix flaky ReplicationLogDiscoveryTest by injecting an advancing clock so rename timestamps are always strictly before the threshold on the next loop iteration.
• Refactor ReplicationLogBaseTest to support configurable aligned vs full-round initial rotation delay, enabling ReplicationLogDiscoveryForwarderTest to use production-aligned rotation.

Test plan

• Existing unit tests pass: ReplicationLogGroupTest, ReplicationLogDiscoveryTest, ReplicationLogDiscoveryForwarderTest
• Ran all HA related integration tests (HABaseIT subclasses)
• Verify RS shutdown logs show Closing all ReplicationLogGroup instances
• Verify failed eager init logs a warning and does not block startup

[tkhurana]

@Himanshu-g81 fixed the flapper test

[Himanshu-g81]

Thanks!