v5-migration

Run `php artisan olm:v5` to migrate v4 tag data to v5 PhotoTags in Laravel, processing category-based tags per user in batched, idempotent runs that prevent memory spikes and long-running transactions.

Yes, specify a single user and adjust the batch size by passing the `--user` and `--batch` options to the `php artisan olm:v5` command, allowing controlled tag processing without memory spikes.

If errors occur during the v4 to v5 data migration, the process logs the errors and continues processing remaining batches. The migrated_at guard ensures failed runs can be retried without creating duplicate PhotoTags.

The migrated_at guard prevents duplicate PhotoTags during batch processing by marking users as processed upon successful migration, ensuring idempotent runs that skip already-migrated data on subsequent executions or retries.

Rebuilding v5 tag structures and generating summaries requires the UpdateTagsService and GeneratePhotoSummaryService, alongside MetricsService and TagKeyCache, to ensure normalized PhotoTags and downstream metrics are correctly calculated.

You need batch processing for Laravel data migration when moving large volumes of v4 category-based tags to v5 normalized PhotoTags, as configurable batch sizes prevent memory spikes and long-running database transactions during per-user processing.