mastodon/db
Eugen Rochko 7dc5035031 Make PreviewCard records reuseable between statuses ()
* Make PreviewCard records reuseable between statuses

**Warning!** Migration truncates preview_cards tablec

* Allow a wider thumbnail for link preview, display it in horizontal layout ()

* Delete preview cards files before truncating

* Rename old table instead of truncating it

* Add mastodon:maintenance:remove_deprecated_preview_cards

* Ignore deprecated_preview_cards in schema definition

* Fix null behaviour
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migrate Make PreviewCard records reuseable between statuses ()
schema.rb Make PreviewCard records reuseable between statuses ()
seeds.rb Fix db:seed - only run some validations when the field was changed ()