Revert commits upto 1.6.0 latest branch

[AjayRajNelapudi]

Changes

This reverts 15 commits for bring 1.6 branch inline with 1.6.0 version.

Reverted commits:

• 8651eb3 Revert commits from b50a5bc to 8ff818a
• 8ff818a Fix release version (Fix release version #118)
• 5776ae3 Revert to JDK 21 and bump version (Revert to Java 21 #117)
• 51d4c82 Bump dependencies and paCommons version (Bump dependencies and paCommons version #116)
• 5b469f2 Bump gradle to v9.2.0 and java to JDK25 ( Bump gradle to v9.2.0 and java to JDK25 #115)
• b40eedb Fix CVE-2025-48924: Bump spotbugs (Fix CVE-2025-48924: Bump spotbugs #113)
• e7d2a14 Bump common version to 2.1.0 (Bump common version to 2.1.0 #106)
• e9dd913 Fix auto-publishing to maven central (Fix auto-publishing to maven central #105)
• 1ef6f64 Update maven publishing workflow to accommodate nexus EOL (Update maven publishing workflow to accommodate nexus EOL #104)
• 8ad6068 Added shard operations metrics constants (Added shard operations metrics constants #103)
• f991f5c Reset 3.0.0 baseline back to jdk 21 (Reset 3.0.0 baseline back to jdk 21 #99)
• 243a9b1 bump java version in maven publish workflow (bump java version in maven publish workflow #98)
• 73c5554 bump spotbug 6.1.5 (bump spotbug 6.1.5 #97)
• b50a5bc bump java 23 (bump java 23 #95)

Retained commits:

• e873e12 Onboarding new maven snapshots publishing to s3 (PA-commons) (Onboarding new maven snapshots publishing to s3 (PA-commons) #111)
• 142be0c Update the maven snapshot publish endpoint and credential (Update the maven snapshot publish endpoint and credential #102)

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Check List

• New functionality includes testing.
  • All tests pass
• New functionality has been documented.
  • New functionality has javadoc added
• Commits are signed per the DCO using --signoff

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[AjayRajNelapudi]

Spot bugs and log4j CVE fixes will be in upcoming PR. This PR is only syncing commits w.r.t branch.

[AjayRajNelapudi]

Spot bugs and log4j CVE fixes will be in upcoming PR. This PR is only syncing commits w.r.t branch.

Updated with 2.19.5 commit and security check succeeded.