This is a leftover for the work done in #14466.

* feat: add possibility of adding WebAuthn security keys to use as 2FA

This adds a basic UI for enabling WebAuthn 2FA. We did a little refactor
to the Settings page for editing the 2FA methods – now it will list the
methods that are available to the user (TOTP and WebAuthn) and from
there they'll be able to add or remove any of them.
Also, it's worth mentioning that for enabling WebAuthn it's required to
have TOTP enabled, so the first time that you go to the 2FA Settings
page, you'll be asked to set it up.
This work was inspired by the one donde by Github in their platform, and
despite it could be approached in different ways, we decided to go with
this one given that we feel that this gives a great UX.

Co-authored-by: Facundo Padula <facundo.padula@cedarcode.com>

* feat: add request for WebAuthn as second factor at login if enabled

This commits adds the feature for using WebAuthn as a second factor for
login when enabled.
If users have WebAuthn enabled, now a page requesting for the use of a
WebAuthn credential for log in will appear, although a link redirecting
to the old page for logging in using a two-factor code will also be
present.

Co-authored-by: Facundo Padula <facundo.padula@cedarcode.com>

* feat: add possibility of deleting WebAuthn Credentials

Co-authored-by: Facundo Padula <facundo.padula@cedarcode.com>

* feat: disable WebAuthn when an Admin disables 2FA for a user

Co-authored-by: Facundo Padula <facundo.padula@cedarcode.com>

* feat: remove ability to disable TOTP leaving only WebAuthn as 2FA

Following examples form other platforms like Github, we decided to make
Webauthn 2FA secondary to 2FA with TOTP, so that we removed the
possibility of removing TOTP authentication only, leaving users with
just WEbAuthn as 2FA. Instead, users will have to click on 'Disable 2FA'
in order to remove second factor auth.
The reason for WebAuthn being secondary to TOPT is that in that way,
users will still be able to log in using their code from their phone's
application if they don't have their security keys with them – or maybe
even lost them.

* We had to change a little the flow for setting up TOTP, given that now
  it's possible to setting up again if you already had TOTP, in order to
  let users modify their authenticator app – given that now it's not
  possible for them to disable TOTP and set it up again with another
  authenticator app.
  So, basically, now instead of storing the new `otp_secret` in the
  user, we store it in the session until the process of set up is
  finished.
  This was because, as it was before, when users clicked on 'Edit' in
  the new two-factor methods lists page, but then went back without
  finishing the flow, their `otp_secret` had been changed therefore
  invalidating their previous authenticator app, making them unable to
  log in again using TOTP.

Co-authored-by: Facundo Padula <facundo.padula@cedarcode.com>

* refactor: fix eslint errors

The PR build was failing given that linting returning some errors.
This commit attempts to fix them.

* refactor: normalize i18n translations

The build was failing given that i18n translations files were not
normalized.
This commits fixes that.

* refactor: avoid having the webauthn gem locked to a specific version

* refactor: use symbols for routes without '/'

* refactor: avoid sending webauthn disabled email when 2FA is disabled

When an admins disable 2FA for users, we were sending two mails
to them, one notifying that 2FA was disabled and the other to notify
that WebAuthn was disabled.
As the second one is redundant since the first email includes it, we can
remove it and send just one email to users.

* refactor: avoid creating new env variable for webauthn_origin config

* refactor: improve flash error messages for webauthn pages

Co-authored-by: Facundo Padula <facundo.padula@cedarcode.com>

* Add support for inlined objects in activity audience

* Add tests

* Fix not being able to unbookmark toots when blocked by their author

* Add tests

* Increase DNS timeout from 1 second to 5 seconds for MX check

1 seconds is rather short when using a recursive DNS resolver which
hasn't got a cached result already available. Use 5 seconds instead,
which is the timeout value we use for outgoing HTTP queries.

* Add more precise error messages for invalid e-mail addresses

* Change content-type to be always computed from file data

Restore previous behavior, detecting the content-type isn't very
expensive, and some instances may serve files as application/octet-stream
regardless of their true type, making fetching media from them fail, while
it used to work pre-3.2.0.

* Add test

* Add tests

* Fix handling of Reject Follow when a matching follow relationship exists

Regression from #12199

* Fix not handling Undo on some activity types when they aren't inlined

When receiving an Undo for a non-inlined activity, try looking it up in
database using the URI. The queries are ad-hoc because we don't have a global
index of object URIs, and not all activity types are stored in database with
an index on their URI.

Announces are just statuses, and have an index on URIs, so this check can
be done efficiently.

Accepts cannot be handled at all because we don't record their URI at any
point.

Follows don't have an index on URI, but they have an index on the issuing
account, which should make such queries largely manageable.

Likes don't have an index on URI, they have an index on the issuing account,
but the number of favs per account may be very high, so I decided not to
handle that.

Blocks don't have an index on URI, but they have an index on the issuing
account, which should make such queries largely manageable.

In all cases, if an Undo could not be handled properly, we call `delete_later!`
because that does not require us to know more than the URI of the undone
property.

* Add tests

* Make newer blocks overwrite older ones

Allows re-synchronizing block info by re-blocking and un-blocking again
when the original Undo Block has been lost.

* Add tests for some cachable responses

This only covers responses that we should have managed to make cachable
so far. It's not the case of all responses that should be cachable in
the end.

* Fix RSS feeds not being cachable

* Fix boosted toots from blocked account not being retroactively removed from TL

Fixes #14301

* Add test for clear_from_timeline

* Fix removing allowed domains being done synchronously

* Add tests

Fixes #14307

* Fix media attachment enumeration

* Switch media_attachments id to snowflake ids

Co-authored-by: Thibaut Girka <thib@sitedethib.com>

* Change move handler to carry blocks and mutes over

When user A blocks user B and B moves to a new account C, make A block C
accordingly.

Note that it only works if A's instance is aware of the Move, that is,
if B is on A's instance or has followers there.

* Also notify instances with known people blocking you when moving

* Add automatic account notes when blocking/muting an account that had no note

* Add UserNote model

* Add UI for user notes

* Put comment in relationships entity

* Add API to create user notes

* Copy user notes to new account when receiving a Move activity

* Address some of the review remarks

* Replace modal by inline edition

* Please CodeClimate

* Button design changes

* Change design again

* Cancel note edition when pressing Escape

* Fixes

* Tweak design again

* Move “Add note” item, and allow users to add notes to themselves

* Rename UserNote into AccountNote, rename “comment” Relationship attribute to “note”

Regression from #14145

- Change audio files to not be stripped of metadata
- Automatically extract cover art from audio if it exists
- Add `thumbnail` parameter to `POST /api/v1/media`, `POST /api/v2/media` and `PUT /api/v1/media/:id`
- Add `icon` to represent it in attachments in ActivityPub
- Fix `preview_url` containing URL of missing missing image when there is no thumbnail instead of null
- Fix duration of audio not being displayed on public pages until the file is loaded

* Split media cleanup from reject-media domain blocks to its own service

* Slightly improve ClearDomainMediaService error handling

* Lower DomainClearMediaWorker to lowest-priority queue

* Do not catch ActiveRecord::RecordNotFound in domain block workers

* Fix DomainBlockWorker spec labels

* Add some specs

* Change domain blocks to immediately mark accounts as suspended

Rather than doing so sequentially, account after account, while cleaning
their data. This doesn't change much about the time the block takes to
complete, but it immediately prevents interaction with the blocked domain,
while up to now, it would only be guaranteed when the process ends.

* Fix serialization of replies when some of them are URIs

Fixes #13956

* Add test

Fixes #13757

* Bump doorkeeper from 5.3.3 to 5.4.0

Bumps [doorkeeper](https://github.com/doorkeeper-gem/doorkeeper) from 5.3.3 to 5.4.0.
- [Release notes](https://github.com/doorkeeper-gem/doorkeeper/releases)
- [Changelog](https://github.com/doorkeeper-gem/doorkeeper/blob/master/CHANGELOG.md)
- [Commits](https://github.com/doorkeeper-gem/doorkeeper/compare/v5.3.3...v5.4.0

)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

* Fix tests

* Fix use of Doorkeeper::AccessToken.find_or_create_for

* Fix tests?

Co-authored-by: dependabot-preview[bot] <27856297+dependabot-preview[bot]@users.noreply.github.com>
Co-authored-by: Thibaut Girka <thib@sitedethib.com>

* Fix sr locale being selected over sr-Latn

* Update tests

Fix #12613

* Add remote only to public timeline

* Fix code style

* Improve RSS entries for statuses

- Render polls in both accounts and tags serializers
- Refactor RSS serializers
- Change title preview to include ellipsis when truncated
- Change title preview to show CW instead of toot text
- Add tests

* Remove title from OEmbed serialization

Twitter doesn't serialize title either, and tihs allows us to move the
title formatting code to the RSS serializers.

Fixes #13612

This reverts commit 05756c9a.