autocomplete: recognize Japanese tags in autocomplete.

Allowing typing Japanese tags in autocomplete. For example, typing 東方
in autocomplete will be completed to the touhou tag. Typing ぶくぶ will
complete to the bkub tag.

This works using wiki page and artist other names. Effectively, any name
listed as an other name in a wiki or artist page will be treated like an
alias for autocomplete purposes. This is limited to non-ASCII other names,
to prevent English other names from interfering with regular tag searches.

app/models/wiki_page.rb

@@ -45,7 +45,7 @@ class WikiPage < ApplicationRecord
 
     def other_names_match(name)
       if name =~ /\*/
-        subquery = WikiPage.from("unnest(other_names) AS other_name").where_ilike("other_name", name)
+        subquery = WikiPage.from("unnest(other_names) AS other_name").where_ilike("other_name", normalize_other_name(name))
         where(id: subquery)
       else
         other_names_include(name)