Check subscription in `answer/show`

app/controllers/answer_controller.rb

@@ -9,6 +9,7 @@ class AnswerController < ApplicationController
 
   def show
     @answer = Answer.includes(comments: %i[user smiles], question: [:user], smiles: [:user]).find(params[:id])
+    @subscribed = Subscription.where(user: current_user, answer: @answer).pluck(:id)
     @display_all = true
 
     if user_signed_in?

app/views/answer/show.html.haml

@@ -1,4 +1,4 @@
 - provide(:title, answer_title(@answer))
 - provide(:og, answer_opengraph(@answer))
 .container-lg.container--main
-  = render 'answerbox', a: @answer, display_all: @display_all
+  = render 'answerbox', a: @answer, display_all: @display_all, subscribed_answer_ids: @subscribed