feat: 関聯する Wiki がない TagLink 修正（#107） (#192)

#107

Co-authored-by: miteruzo <miteruzo@naver.com>
Reviewed-on: #192

backend/app/controllers/wiki_pages_controller.rb

@@ -13,6 +13,22 @@ class WikiPagesController < ApplicationController
     render_wiki_page_or_404 WikiPage.find_by(title: params[:title])
   end
 
+  def exists
+    if WikiPage.exists?(params[:id])
+      head :no_content
+    else
+      head :not_found
+    end
+  end
+
+  def exists_by_title
+    if WikiPage.exists?(title: params[:title])
+      head :no_content
+    else
+      head :not_found
+    end
+  end
+
   def diff
     id = params[:id]
     from = params[:from]