[To dev/1.3] Fix pipe TsFile transfer when mod file is missing (#18756)

[Caideyipi]

Description

Backport #18756 (commit 4092a78) to dev/1.3.

Missing modification file handling

• Downgrade to a TsFile-only transfer when the modification sidecar disappears before it is opened.
• Rebuild the conversion task information after the transfer mode changes.
• Stop retrying a permanently missing TsFile after five attempts and report a critical sink exception while retaining the event for cleanup.

Backport adaptation

• Resolved the async sink and TsFile handler conflicts against the dev/1.3 APIs.
• Kept the branch's existing logging and database-name conventions.

Verification

• mvn spotless:apply -pl iotdb-core/datanode
• mvn test -pl iotdb-core/datanode -Dtest=IoTDBDataRegionAsyncSinkTest,PipeTransferTsFileHandlerCleanupTest
• Tests run: 9, failures: 0, errors: 0, skipped: 0.

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This PR has:

• been self-reviewed.
• added comments explaining the why and intent of non-obvious code.
• added or updated unit tests to cover the new code paths.

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Key changed/added classes (or packages if there are too many classes) in this PR

• IoTDBDataRegionAsyncSink
• PipeTransferTsFileHandler
• IoTDBDataRegionAsyncSinkTest
• PipeTransferTsFileHandlerCleanupTest