Fix deletion visibility in region migration IT

[Caideyipi]

Summary

• wait for migrated region replicas to receive and close the initial TsFile before issuing deletion
• wait for deletion mods on initial replicas and the destination replica after migration
• share region migration file/replica assertions between tree and table ITs

Tests

• mvn spotless:apply -pl integration-test -P with-integration-tests
• git diff --check
• Target table IT was attempted locally, but the Windows environment could not start the full 1C3D cluster: default JVM settings failed with pagefile exhaustion; reduced heap failed during DataNode startup with unable to create native thread before test SQL executed.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 41.37%. Comparing base (b4c4e54) to head (513e324).

Additional details and impacted files

@@             Coverage Diff              @@
##             master   #18065      +/-   ##
============================================
- Coverage     41.50%   41.37%   -0.14%     
  Complexity      318      318              
============================================
  Files          5287     5287              
  Lines        370752   370752              
  Branches      47985    47985              
============================================
- Hits         153893   153411     -482     
- Misses       216859   217341     +482     

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