Backport 6515,6538,6559 to release v2.10#6646

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zhxiaogg wants to merge 3 commits intografana:release-v2.10from

zhxiaogg:backport-6515-to-release-v2.10

Commits on Mar 10, 2026

enhancement: use frontend MaxExemplars config as single source of truth for exemplar limits (#6515)
zhxiaogg
committed
refactor: removed execess exemplars param from CompileMetricsQueryRange (#6538)
zhxiaogg
committed
bugfix: apply exemplars hint end-to-end and fix safety cap bypass (#6559)
zhxiaogg
committed