Fix global lock contention in `DistClusterControllerStateModel` caused by `Optional.empty()` singleton#3052

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LZD-PratyushBhatt wants to merge 3 commits intoapache:masterfrom

LZD-PratyushBhatt:fix_global_lock_contention

Commits on Jun 28, 2025

Fix global lock contention in DistClusterControllerStateModel caused by Optional.empty() singleton
LZD-PratyushBhatt
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Commits on Jun 30, 2025

Address review comments
LZD-PratyushBhatt
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Commits on Jul 7, 2025

Address review comments and add a new test for explictly testing two locks
LZD-PratyushBhatt
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