[ISSUE #10218] Fix resource leak in DumpCompactionLogCommand

[daguimu]

Problem

DumpCompactionLogCommand.execute() creates a RandomAccessFile to obtain a FileChannel, but neither resource is ever closed. The anonymous RandomAccessFile is immediately discarded after .getChannel(), making it impossible to close. This leaks file descriptors on every invocation.

Root Cause

The code uses new RandomAccessFile(fileName, "rw").getChannel() as a one-liner, discarding the RandomAccessFile reference. Neither the RandomAccessFile nor the FileChannel is wrapped in a try-with-resources block or closed in a finally block.

Fix

• Wrap both RandomAccessFile and FileChannel in a try-with-resources statement to ensure they are always closed after use.
• Changed the file mode from "rw" to "r" since the command only reads (dumps) the compaction log, it does not need write access. The MapMode was also changed from READ_WRITE to READ_ONLY to match.

Tests Added

Change Point	Test
try-with-resources for resource cleanup	testExecuteWithValidFile() — writes a message, dumps it, verifies no resource leak (file still accessible)
Read-only mode handles empty files	testExecuteWithEmptyFile() — verifies graceful handling of empty files
Non-existent file throws exception	testExecuteWithNonExistentFile() — verifies SubCommandException is thrown
Missing -f option	testExecuteWithoutFileOption() — verifies error message is printed without exception

Impact

Only affects the dumpCompactionLog CLI tool. No changes to broker runtime or message processing logic.

Fixes #10218

[codecov-commenter]

Codecov Report

❌ Patch coverage is 76.19048% with 5 lines in your changes missing coverage. Please review.
✅ Project coverage is 48.87%. Comparing base (932588d) to head (7eaff91).

Files with missing lines	Patch %	Lines
...ools/command/message/DumpCompactionLogCommand.java	76.19%	3 Missing and 2 partials ⚠️

Additional details and impacted files

@@              Coverage Diff              @@
##             develop   #10219      +/-   ##
=============================================
- Coverage      48.96%   48.87%   -0.09%     
+ Complexity     13385    13365      -20     
=============================================
  Files           1373     1373              
  Lines          99904    99907       +3     
  Branches       12901    12902       +1     
=============================================
- Hits           48913    48827      -86     
- Misses         45062    45133      +71     
- Partials        5929     5947      +18     

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