Fix import regression for ActiveStorage::VariantRecord attachments

[Mouxy]

ActiveStorage::VariantRecord (image thumbnails/resizes) was missing from INTERNAL_RECORD_TYPES, causing IntegrityError during import check when the export ZIP contained variant record attachments.

This is a follow-up to #2707 which handled Export and Account::Import but missed this third internal type.

• Add ActiveStorage::VariantRecord to INTERNAL_RECORD_TYPES
• Filter variant blobs/files during import of old exports
• Skip variant attachments during import check and import phases

[Copilot]

Pull request overview

This PR fixes an import regression by adding support for filtering ActiveStorage::VariantRecord attachments and their associated blobs from account exports and imports. Previously, ActiveStorage::VariantRecord was not recognized as an internal record type, causing IntegrityError exceptions during import when exports contained variant record attachments. This is a follow-up to PR #2707 which addressed similar issues with Export and Account::Import record types.

Changes:

• Added ActiveStorage::VariantRecord to the INTERNAL_RECORD_TYPES constant in RecordSet
• Updated blob and file record sets to identify and skip variant blobs during export and import
• Added AttachmentRecordSet logic to skip internal attachments during import check and import phases
• Comprehensive test coverage including export validation, blob/file filtering, and attachment handling

Reviewed changes

Copilot reviewed 8 out of 8 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
app/models/account/data_transfer/record_set.rb	Added ActiveStorage::VariantRecord to INTERNAL_RECORD_TYPES constant
app/models/account/data_transfer/active_storage/blob_record_set.rb	Added logic to identify and skip internal blobs during import
app/models/account/data_transfer/active_storage/file_record_set.rb	Added logic to identify and skip internal blob storage files during import and check
app/models/account/data_transfer/active_storage/attachment_record_set.rb	Added check and import filtering for internal record type attachments
test/models/account/export_test.rb	Added test verifying exports exclude variant record attachments and blobs
test/models/account/data_transfer/active_storage/blob_record_set_test.rb	Added test verifying internal blobs are skipped during import
test/models/account/data_transfer/active_storage/file_record_set_test.rb	Added tests for skipping internal blob storage files
test/models/account/data_transfer/active_storage/attachment_record_set_test.rb	New test file covering attachment record set filtering

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[Mouxy]

@flavorjones, I noticed this problem when I tried to import my account into a new "once" deployment I was testing, so I tried this end-to-end with a real account export ZIP.

I exported the file, then manually patched the ZIP by removing ActiveStorage::VariantRecord related data (variant attachment records and their linked blob metadata), and re-imported it.

The import completed successfully after that change.

This aligns with the fix in this PR (excluding/skipping variant-derived internal records during export/import).