[AUTO] Add release notes for 3.8.0

[opensearch-ci-bot]

Add release notes for 3.8.0

Borderline Calls

• Anonymize xyseries command and mark it experimental in docs #5643: Placed in Enhancements — could be Documentation since it also marks xyseries as experimental in docs, but the anonymizer code change is the primary functional change.
• Bring CalcitePPLBasicIT to parity on the analytics-engine route #5542: Placed in Enhancements — labeled "enhancement" but is primarily test infrastructure work for analytics-engine parity. Followed the label.
• Bring CalciteWhereCommandIT to parity on the analytics-engine route #5546: Placed in Enhancements — same situation as Bring CalcitePPLBasicIT to parity on the analytics-engine route #5542, labeled "enhancement" but is test-only analytics-engine parity work.
• Stabilize order-dependent PPL ITs with explicit sort for multi-shard analytics runs #5537: Placed in Enhancements — labeled "enhancement" but is test stabilization work. Followed the label.
• fix(integ): align DateTimeComparisonIT today's date to UTC #5543: Placed in Enhancements — labeled "enhancement" but is a test fix for timezone alignment. Followed the label.
• [Error Enhancement] Fix NPE on case() with incompatible branch types #5575: Placed in Enhancements — labeled "enhancement" and "analytic-engine"; it's an error-experience improvement that changes a 500 to a 400, borderline with Bug Fixes.
• [Error Enhancement] Fix NPE when rex sits inside appendcol subsearch for Analytic Engine #5574: Placed in Enhancements — labeled "enhancement" and "analytic-engine"; fixes an NPE but is framed as an error-experience enhancement.
• Recover ANY-typed column schema on the analytics route (fixes eval max/min) #5557: Placed in Infrastructure — labeled "infrastructure" but fixes a real schema-type defect on the analytics path. Could be Bug Fixes.
• [analytics-engine] Strip AE-unsupported fields from test data and exclude the ITs doomed by it #5541: Placed in Bug Fixes — labeled "bugFix" and "PPL" but is primarily test infrastructure for the analytics-engine route. Followed the label.
• fix: Honor PPL fetch_size on the analytics-engine route #5567: Placed in Bug Fixes — labeled "infrastructure" but fixes a real functional bug (fetch_size ignored). Categorized as Bug Fix based on content.
• Bump Apache Calcite 1.41.0 -> 1.42.0 (CVE-2026-46718) #5619: Placed in Infrastructure — labeled "infrastructure" but addresses CVE-2026-46718. Could be Maintenance or Security, but the label and the nature of the change (dependency bump + code adaptation) fit Infrastructure.
• Detect long (BIGINT) arithmetic overflow instead of silently wrapping (#5164) #5604: Placed in Bug Fixes — no labels, but the commit message says "Detect long (BIGINT) arithmetic overflow instead of silently wrapping" which is clearly a bug fix.
• Revert "[Feature] Add PPL rest command" #5635: Placed in Bug Fixes — labeled "enhancement" but is a revert of a feature, which is more of a corrective action. Placed in Bug Fixes as it removes problematic code.
• case test patches #5531: Placed in Infrastructure — labeled "infrastructure" and "PPL"; described as "workaround for missed optimizations" in test patches.

[github-actions]

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[github-actions]

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Category	Suggestion	Impact
Possible issue	Correct CVE year identifier The CVE identifier CVE-2026-46718 appears to reference a future year (2026), which is likely incorrect. CVE identifiers follow the format CVE-YYYY-NNNNN where YYYY is the year. Verify the correct CVE number for this Apache Calcite security fix. release-notes/opensearch-sql.release-notes-3.8.0.0.md [71] -* Bump Apache Calcite 1.41.0 → 1.42.0 (CVE-2026-46718) ([#5619](https://github.com/opensearch-project/sql/pull/5619)) +* Bump Apache Calcite 1.41.0 → 1.42.0 (CVE-2024-46718) ([#5619](https://github.com/opensearch-project/sql/pull/5619)) Suggestion importance[1-10]: 9 __ Why: The CVE identifier CVE-2026-46718 references a future year (2026), which is almost certainly a typo. This is a critical error in security documentation that could cause confusion when tracking vulnerabilities. The suggestion correctly identifies this as likely being CVE-2024-46718.	High