Tag change notices

This adds a small notice at the bottom of post searches if a single tag search is the target of any tag change request.

app/models/bulk_update_request.rb

@@ -16,6 +16,7 @@ class BulkUpdateRequest < ApplicationRecord
   before_validation :initialize_attributes, :on => :create
   before_validation :normalize_text
   after_create :create_forum_topic
+  after_save :update_notice
 
   scope :pending_first, -> { order(Arel.sql("(case status when 'pending' then 0 when 'approved' then 1 else 2 end)")) }
   scope :pending, -> {where(status: "pending")}
@@ -241,4 +242,11 @@ class BulkUpdateRequest < ApplicationRecord
   def estimate_update_count
     AliasAndImplicationImporter.new(script, nil).estimate_update_count
   end
+
+  def update_notice
+    TagChangeNoticeService.update_cache(
+      AliasAndImplicationImporter.new(script, nil).affected_tags,
+      forum_topic_id
+    )
+  end
 end

app/models/tag_relationship.rb

@@ -32,6 +32,7 @@ class TagRelationship < ApplicationRecord
   validates :approver, presence: { message: "must exist" }, if: -> { approver_id.present? }
   validates :forum_topic, presence: { message: "must exist" }, if: -> { forum_topic_id.present? }
   validate :antecedent_and_consequent_are_different
+  after_save :update_notice
 
   def initialize_creator
     self.creator_id = CurrentUser.user.id
@@ -196,6 +197,13 @@ class TagRelationship < ApplicationRecord
     Post.fast_count(antecedent_name, skip_cache: true)
   end
 
+  def update_notice
+    TagChangeNoticeService.update_cache(
+      [antecedent_name, consequent_name],
+      forum_topic_id
+    )
+  end
+
   extend SearchMethods
   include MessageMethods
 end