Reduce indirection. PostSet is basically a collection of helper methods
for rendering the post index page. PostSetPresenter was a set of helper
methods for rendering the tag list on the post index page. These don't
need to be separated.
Make PostQueryBuilder apply aliases earlier, immediately after parsing
the search.
On the post index page there are multiple places where we need to apply
aliases:
* When running the search with PostQueryBuilder#build.
* When calculating the search count with PostQueryBuilder#fast_count.
* When calculating the related tags for the sidebar.
* When tracking missed searches and popular searches for Reportbooru.
* When looking up wiki excerpts.
Applying aliases after parsing ensures we only have to apply aliases
once for all of these things.
We also normalize the order of tags in searches and strip repeated tags.
This is so that we have consistent cache keys for fast_count.
* Fixes searches for aliased tags being counted as missed searches (fixes#4433).
* Fixes wiki excerpts not showing up when searching for aliased tags.
* Move various search parser helper methods (`has_metatag?`,
`is_single_tag?` et al) from PostSets and the Tag model to
PostQueryBuilder.
* Fix various minor bugs stemming from trying to check if a search query
contains certain metatags using regexes or other adhoc techniques.
Change the title of the post index page to look like this:
"Danbooru: Anime Image Board" (for the front page)
"Kantai Collection Art | Danbooru" (for a tag search)
Change the meta description of the front page to look like this:
Danbooru is the original anime image 'booru. Find over 3.75 million
anime pictures categorized by over 100 million tags.
Change the meta description for a tag search to look like this:
Find over 37,168 Azur Lane images on Danbooru. Azur Lane (碧蓝航线)
(벽람항로) is a Chinese shipgirl-themed side-scrolling shoot 'em up
mobile game developed by Shanghai Manjuu and Xiamen Yongshi...
* Factor out common sidebar layout template.
* Convert wiki pages and posts to use this template.
* Add data-layout attribute to <body> element indicating the current layout.
This causes the browser to prefetch the next page in a search, which may
make browsing seem faster to the end user, but it effectively doubles
the load on the server.
Avoid some queries used in wiki page excerpts:
* Only try to load the artist if the tag is an artist tag.
* Avoid using `exists?` queries for wiki pages.
* Bugfix: don't show wiki excerpts for deleted wikis.
Refactor tag_list_html, split_tag_list_html, and inline_tag_list_html to
take the `show_extra_links` and `current_query` options explicitly,
rather than implicitly relying on CurrentUser or taking `params[:tags]`
from the template.
