[MarioPym]

Summary

Some core migrations add columns and indexes without checking first whether they already exist. On a clean upgrade this is fine, but when a migration runs again (for example after an interrupted upgrade, in our case from 29 to 33, or on a schema that already has these columns), the upgrade stops with "already exists" errors and the migration is never recorded as done.

This adds hasColumn() / hasIndex() checks to:

• Version30000Date20240815080800 (webauthn.user_verification)
• Version31000Date20240814184402 (preferences lazy/type/flags/indexed columns and their indexes)
• Version33000Date20251023120529 (unique_bucket_store index on preview_locations)

This follows the same pattern already used in Version30000Date20240717111406 and in the files_trashbin migrations.

Checklist

• Code is properly formatted
• Sign-off message is added to all commits
• Tests (unit, integration, api and/or acceptance) are included
• Screenshots before/after for front-end changes
• Documentation (manuals or wiki) has been updated or is not required
• Backports requested where applicable (ex: critical bugfixes)
• Labels added where applicable (ex: bug/enhancement, 3. to review, feature component)
• Milestone added for target branch/version (ex: 32.x for stable32)

AI (if applicable)

• The content of this PR was partly or fully generated using AI

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[come-nc]

I would say the tests for migrations are overkill, migration code is not expected to change that much, we should not add a test for each migration like this.

[MarioPym]

I would say the tests for migrations are overkill, migration code is not expected to change that much, we should not add a test for each migration like this.

Makes sense, I removed the migration tests.