* Add index on posts.is_deleted. The modqueue was slow because we the
appeal condition wasn't constrained to deleted posts, so it degraded to
a full table scan.
* Avoid extra queries for calculating the page count and disapproval counts.
* Include appealed posts in the modqueue.
* Add `status` field to appeals. Appeals start out as `pending`, then
become `rejected` if the post isn't approved within three days. If the
post is approved, the appeal's status becomes `succeeded`.
* Add `status` field to flags. Flags start out as `pending` then become
`rejected` if the post is approved within three days. If the post
isn't approved, the flag's status becomes `succeeded`.
* Leave behind a "Unapproved in three days" dummy flag when an appeal
goes unapproved, just like when a pending post is unapproved.
* Only allow deleted posts to be appealed. Don't allow flagged posts to be appealed.
* Add `status:appealed` metatag. `status:appealed` is separate from `status:pending`.
* Include appealed posts in `status:modqueue`. Search `status:modqueue order:modqueue`
to view the modqueue as a normal search.
* Retroactively set old flags and appeals as succeeded or rejected. This
may not be correct for posts that were appealed or flagged multiple
times. This is difficult to set correctly because we don't have
approval records for old posts, so we can't tell the actual outcome of
old flags and appeals.
* Deprecate the `is_resolved` field on post flags. A resolved flag is a
flag that isn't pending.
* Known bug: appealed posts have a black border instead of a blue
border. Checking whether a post has been appealed would require either
an extra query on the posts/index page, or an is_appealed flag on
posts, neither of which are very desirable.
* Known bug: you can't use `status:appealed` in blacklists, for the same
reason as above.
Some searches, such as searches for private favorites or for the
status:unmoderated tag, return different results for different users.
These searches need to have their counts cached separately for each user
so that we don't return incorrect page counts when two different users
perform the same search.
This can also potentially leak private information, such as the number
of posts flagged, downvoted, or disapproved by a given user.
Partial fix for #4280.
* Add options for changing the order of the modqueue (newest first,
oldest first, highest scoring first, lowest scoring first).
* Change the default order from oldest posts first to most recently
flagged or uploaded posts first.
* Add an order:modqueue metatag to order by most recently flagged or
uploaded in standard searches.
Add a sidebar to the modqueue page that shows the following information:
* Number of pending and flagged posts.
* Number of posts disapproved for poor quality or breaking rules.
* Top uploaders in the queue.
* Top artist, copyright, and character tags in the queue.
