Add posts, tags, tagging, to database. Create references to align with new DB model. Add image of mermaid template model.

app/models/image.rb

@@ -1,5 +1,8 @@
 class Image < ApplicationRecord
   has_one_attached :file
 
+  has_many :taggings, as: :taggable
+  has_many :tags, through: :taggings
+
   validates :title, :file, presence: true
 end