[ISSUE #10462] Fix resource leaks and lifecycle issues

[lizhimins]

What is the purpose of the change

Part of #10462

Fix resource leaks and improve lifecycle management in tiered storage module.

Brief changelog

• FileSegment close() waits for in-flight commit (30s timeout)
• PosixFileSegment: store RAF references to prevent handle leaks
• MessageStoreExecutor shutdown(): add awaitTermination(30s)
• Remove MessageStoreExecutor singleton pattern
• Remove fileRecyclingExecutor (wrong thread name, unused)
• Change MessageStoreExecutor fields from public to private with getters
• FlatFileFactory: remove test constructor that leaked thread pool
• FlatMessageFile: remove dead inFlightRequestMap field
• TieredMessageStore: reorder shutdown (dispatcher->index->executor->file->next)
• Update all tests to pass executor to FlatFileFactory and shutdown in @after

Verifying this change

• mvn compile succeeds
• mvn test -pl tieredstore passes (112 tests, 0 failures)

🤖 Generated with Claude Code

[codecov-commenter]

Codecov Report

❌ Patch coverage is 73.17073% with 11 lines in your changes missing coverage. Please review.
✅ Project coverage is 48.01%. Comparing base (a6fb9e2) to head (f707726).
⚠️ Report is 10 commits behind head on develop.

Files with missing lines	Patch %	Lines
...che/rocketmq/tieredstore/MessageStoreExecutor.java	50.00%	5 Missing and 2 partials ⚠️
...pache/rocketmq/tieredstore/TieredMessageStore.java	60.00%	0 Missing and 2 partials ⚠️
...che/rocketmq/tieredstore/provider/FileSegment.java	66.66%	2 Missing ⚠️

Additional details and impacted files

@@              Coverage Diff              @@
##             develop   #10476      +/-   ##
=============================================
- Coverage      48.03%   48.01%   -0.03%     
- Complexity     13286    13301      +15     
=============================================
  Files           1376     1377       +1     
  Lines         100558   100646      +88     
  Branches       12985    12999      +14     
=============================================
+ Hits           48305    48325      +20     
- Misses         46333    46380      +47     
- Partials        5920     5941      +21     

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[oss-sentinel-ai]

Review: Approved ✅

PR: #10476 — Fix resource leaks and lifecycle issues
Type: Bug fix (18 files, +108/-63)

Assessment

Fixes resource leaks in tiered storage: FileSegment close() waits for in-flight commits, PosixFileSegment stores RAF references to prevent handle leaks, MessageStoreExecutor shutdown improvements.

Verdict

✅ Solid resource management fixes. Part of #10462.

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🤖 Automated review by oss-sentinel-ai