Support serializing plain device time index

[shuwenwei]

Description

Support serializing plain device time index

[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 39.69%. Comparing base (0012727) to head (d0aa2cf).
⚠️ Report is 2 commits behind head on master.

Additional details and impacted files

@@             Coverage Diff              @@
##             master   #17285      +/-   ##
============================================
- Coverage     39.70%   39.69%   -0.01%     
  Complexity      282      282              
============================================
  Files          5100     5100              
  Lines        341950   341966      +16     
  Branches      43559    43560       +1     
============================================
- Hits         135769   135747      -22     
- Misses       206181   206219      +38     

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[Copilot]

Pull request overview

This PR updates time index serialization behavior to migrate legacy (plain) device time indexes into the newer array-based format when writing resources, and adds a regression test to validate repairing/moving an old-version resource file results in an ArrayDeviceTimeIndex.

Changes:

• Add a compaction repair test that loads a v3 tsfile + legacy resource file and validates the repaired resource uses ARRAY_DEVICE_TIME_INDEX_TYPE.
• Remove PlainDeviceTimeIndex’s unsupported serialize override so it can be written using the array-format serializer.
• Adjust ArrayDeviceTimeIndex.serialize to always write the array time index type marker.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
iotdb-core/datanode/src/test/java/org/apache/iotdb/db/storageengine/dataregion/compaction/repair/RepairUnsortedFileCompactionTest.java	Adds coverage for repairing/moving an old-version resource and asserting time index type migration to array format.
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/storageengine/dataregion/tsfile/timeindex/PlainDeviceTimeIndex.java	Enables serialization (via inherited serializer) by removing the previous UnsupportedOperationException serialize override.
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/storageengine/dataregion/tsfile/timeindex/ArrayDeviceTimeIndex.java	Forces serialized time index type marker to ARRAY_DEVICE_TIME_INDEX_TYPE to support migration-on-write behavior.

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