Show author names in problem and translation views

app/models/translation.rb

@@ -1,5 +1,6 @@
 class Translation < ApplicationRecord
   belongs_to :problem, inverse_of: :translations
+  belongs_to :author, class_name: 'User', inverse_of: :translations, optional: true
   enum status: [:pending, :in_use, :outdated, :declined]
 
   validates :title, :content, :problem_id, presence: true
@@ -7,6 +8,10 @@ class Translation < ApplicationRecord
 
   self.per_page = 50
 
+  def has_author?
+    !!self.author
+  end
+
   def title_is_unique_among_other_problems
     Problem.includes(:translation).where.not(id: problem_id).each do |problem|
       if problem.is_translated? and problem.title == title