* Fix Sidekiq warnings about JSON serialization

This occurs on every symbol argument we pass, and every symbol key in hashes,
because Sidekiq expects strings instead.

See https://github.com/mperham/sidekiq/pull/5071

We do not need to change how workers parse their arguments because this has
not changed and we were already converting to symbols adequately or using
`with_indifferent_access`.

* Set Sidekiq to raise on unsafe arguments in test mode

In order to more easily catch issues that would produce warnings in production
code.

* Add trending links

* Add overriding specific links trendability

* Add link type to preview cards and only trend articles

Change trends review notifications from being sent every 5 minutes to being sent every 2 hours

Change threshold from 5 unique accounts to 15 unique accounts

* Fix tests

* Add followed_by? to account_interactions

* Add RemoveFromFollowersService

* Fix AccountBatch to use RemoveFromFollowersService

* Add remove from followers API

Fixes #15273

Co-authored-by: Claire <claire.github-309c@sitedethib.com>

About 2x speed-up on inboxes query

* Add follow selected followers button

* Fix unused variable

* Fix i18n normalize

There are edge cases where requests to certain hosts timeout when
using the vanilla HTTP.rb gem, which the goldfinger gem uses. Now
that we no longer need to support OStatus servers, webfinger logic
is so simple that there is no point encapsulating it in a gem, so
we can just use our own Request class. With that, we benefit from
more robust timeout code and IPv4/IPv6 resolution.

Fix #14091

Instead, just re-use the existing category if any.

Fixes #12608

Change inaccurate labels on other admin settings

Fix #11913

Fix #10736

- Change data export to be available for non-functional accounts
- Change non-functional accounts to include redirecting accounts

Fix #3961

Not a serious issue because they are meaningless past single use

* Fix 2FA challenge not appearing for non-database users

Fix #11685

* Fix account deletion not working when using external login

Fix #11691

Change all account actions except "none" to resolve all unresolved reports

Refactor `SuspendAccountService` to be more readable

* Add soft delete for statuses to allow them to appear instant

* Allow reporting soft-deleted statuses and show them in the admin UI

* Change index for getting an account's statuses

The reason for unattaching media instead of removing it is to support
delete & redraft functionality, but remote or staff-removed statuses
will never be redrafted, so the media should be deleted immediately

* Add automatic blocklist display in /about/blocks

Inspired by https://github.com/Gargron/mastodon.social-misc

* Add admin option to set who can see instance blocks

* Normalize locales files

* Rename “Sandbox” to “Silence” for consistency

* Disable /about/blocks when in whitelist mode

* Optionally display rationale for domain blocks

* Only display domain blocks that have user-facing limitations, and order them

* Redesign table of blocked domains to better handle long domain names and rationales

* Change domain blocks ordering now that rationales aren't displayed right away

* Only show explanation for block severities actually in use

* Reword instance block explanations and add disclaimer for public fetch mode

* Add environment variable to disable the anti-spam

* Move antispam setting to admin settings

* Fix typo

* antispam → spam_check

* Record deleted(by mod) status to prevent re-appear

* Move to Tombstone

* Add missing migration script

* Check if image value is nil? before creating an image

Check if uploaded images aren't nil before creating SiteUpload models
for them.

* Validate presence of file in SiteUpload

* Fix file presence validation

* Fabricate SiteUpload#file

* Add link to Creative Commons license

These will allow these images to be uploaded again on the admin settings
page.

* Add validations to admin settings

- Validate correct HTML markup
- Validate presence of contact username & e-mail
- Validate that all usernames are valid
- Validate that enums have expected values

* Fix code style issue

* Fix tests

Fix #6856
Fix #6951

* Add moderation warnings

Replace individual routes for disabling, silencing, and suspending
a user, as well as the report update route, with a unified account
action controller that allows you to select an action (none,
disable, silence, suspend) as well as whether it should generate an
e-mail notification with optional custom text. That notification,
with the optional custom text, is saved as a warning.

Additionally, there are warning presets you can configure to save
time when performing the above.

* Use Account#local_username_and_domain

* Add instance-wide setting to disable profile directory

Fixes #9496

When the profile directory is disabled:
- The “discoverable” setting is hidden from users
- The “profile directory” link is not shown on public pages
- /explore returns 404

* Move Setting.profile_directory check to a before_action filter

Fix #3894

* Add default_settings class method to ScopedSettings

ScopedSettings was extended to use value of unscoped setting instead of
only using defaults set in config/settings.yml for selected settings.
This adds possibility for admins to set default values of users' settings,
for example default theme (as requested in #7092).

* Add ability to change an instance default theme

Closes #7092

* Add confirmation page for suspensions

* Suspension confirmation closes reports, linked from report UI

* Fix tests

* Add separate setting for sidebar text (site_short_description)

* Fix tests