Add user preference to always expand toots marked with content warnings (#8762)

app/controllers/settings/preferences_controller.rb

app/javascript/mastodon/actions/importer/normalizer.js

app/javascript/mastodon/initial_state.js

app/lib/user_settings_decorator.rb

app/models/user.rb

app/serializers/initial_state_serializer.rb

app/views/settings/preferences/show.html.haml

app/views/stream_entries/_detailed_status.html.haml

app/views/stream_entries/_simple_status.html.haml

config/locales/simple_form.en.yml

config/settings.yml