fix: avoid skipping orphan file records

[efegokdemir]

Summary

Fixes #1631.

CleanOrphanUploadFiles currently requests page 2 after mutating the page-1 rows from status=available to status=deleted. Because the filtered result set shrinks, offset pagination can skip records.

This change repeatedly reads the first page while cleanup changes the result set, and stops when a pass makes no progress. This preserves the existing behavior for recent or referenced files while ensuring later eligible records are examined.

Changes

• Re-read the first available page after cleanup changes status or repairs a file record.
• Stop when no record was changed, preventing repeated scans of retained records.
• Add a regression test with 1,001 orphan records to cover the page-boundary skip.

Testing

• go test ./internal/service/file_record ./internal/repo/file_record -count=1
• go vet ./internal/service/file_record ./internal/repo/file_record
• git diff --check

The focused regression test fails on the pre-fix implementation because record 1,001 remains available, and passes with this change.

AI assistance

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