BURs: fix validation error when aliasing tags with implications.

Bug: when aliasing a tag that implied another tag, it was possible for
the alias to fail. Moving the implication could fail because we checked
that the tag category of both tags in the implication was the same, but
we did this before the alias moved the category of the old tag to the
new tag.

app/logical/tag_mover.rb

@@ -9,10 +9,10 @@ class TagMover
 
   def move!
     CurrentUser.scoped(user) do
+      move_tag_category!
       move_aliases!
       move_implications!
       move_cosplay_tag!
-      move_tag_category!
       move_artist!
       move_wiki!
       move_saved_searches!

app/models/tag_implication.rb

@@ -11,7 +11,7 @@ class TagImplication < TagRelationship
   validate :absence_of_transitive_relation
   validate :antecedent_is_not_aliased
   validate :consequent_is_not_aliased
-  validate :tag_categories_are_compatible
+  validate :tag_categories_are_compatible, on: :request
   validate :meets_tag_size_requirements, on: :request
   validate :has_wiki_page, on: :request
 

test/unit/bulk_update_request_test.rb

@@ -82,6 +82,18 @@ class BulkUpdateRequestTest < ActiveSupport::TestCase
           assert_equal(true, TagImplication.where(antecedent_name: "ddd", consequent_name: "ccc", status: "active").exists?)
         end
 
+        should "allow moving a copyright tag that implies another copyright tag" do
+          @t1 = create(:tag, name: "komeiji_koishi's_heart_throbbing_adventure", category: Tag.categories.general)
+          @t2 = create(:tag, name: "komeiji_koishi_no_dokidoki_daibouken", category: Tag.categories.copyright)
+          @t3 = create(:tag, name: "touhou", category: Tag.categories.copyright)
+          create(:tag_implication, antecedent_name: "komeiji_koishi_no_dokidoki_daibouken", consequent_name: "touhou")
+
+          create_bur!("alias komeiji_koishi_no_dokidoki_daibouken -> komeiji_koishi's_heart_throbbing_adventure", @admin)
+
+          assert_equal(true, @t1.reload.copyright?)
+          assert_equal(true, TagImplication.exists?(antecedent_name: "komeiji_koishi's_heart_throbbing_adventure", consequent_name: "touhou"))
+        end
+
         should "allow aliases to be reversed in one step" do
           @alias = create(:tag_alias, antecedent_name: "aaa", consequent_name: "bbb")
           @bur = create_bur!("create alias bbb -> aaa", @admin)