Eugen Rochko 88725d6ce8 OEmbed support for PreviewCard ()
* OEmbed support for PreviewCard

* Improve ProviderDiscovery code failure treatment

* Do not crawl links if there is a content warning, since those
don't display a link card anyway

* Reset db schema

* Fresh migrate

* Fix rubocop style issues
Fix  - return existing access token when applicable instead of creating new

* Fix test

* Extract http client to helper

* Improve oembed controller
..
activitypub Change ActivityPub paging to match spec. Clean up ActivityPub outbox changes. ()
v1 Fix - Add Idempotency-Key header to PostStatusService that prevents ()
web Home column filters
oembed_controller.rb OEmbed support for PreviewCard ()
push_controller.rb Punycode URI normalization ()
salmon_controller.rb Move Salmon processing to background as well as PuSH
subscriptions_controller.rb Fix rubocop issues, introduce usage of frozen literal to improve performance