HBASE-30246 MOB compaction does not close MobCell after resolving ref…

[liuxiaocs7]

…erence cells (#8422)

(cherry picked from commit 8667763)
(cherry picked from commit 5ba181e)

[Copilot]

Pull request overview

Fixes MOB compaction/resolve lifecycle handling by ensuring MobCell instances are properly closed after resolving reference cells, while also returning an independent heap copy of the resolved cell to avoid later use-after-release of scanner-backed buffers during compaction.

Changes:

• Add DefaultMobStoreCompactor#resolveMobCell to resolve a MOB reference, deep-copy the resolved Cell, and close the underlying MobCell.
• Update compaction paths (and the faulty compactor test helper) to use resolveMobCell instead of directly using the scanner-backed resolved cell.
• Strengthen tests to enforce MobCell closure and independence of the returned Cell, and update existing resolve test to close MobCell via try-with-resources.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
hbase-server/src/main/java/org/apache/hadoop/hbase/mob/DefaultMobStoreCompactor.java	Introduces resolveMobCell to close MobCell and return a heap-resident copy safe for compaction writer retention.
hbase-server/src/test/java/org/apache/hadoop/hbase/mob/FaultyMobStoreCompactor.java	Switches reference-cell resolution to resolveMobCell to match corrected ownership/closure behavior.
hbase-server/src/test/java/org/apache/hadoop/hbase/mob/TestDefaultMobStoreCompactor.java	Adds a unit test verifying resolveMobCell closes the MobCell and returns an independent copy.
hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestHMobStore.java	Updates testResolve to close returned MobCell instances using try-with-resources.

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