Revert "Set default "Untitled" title for published cards"

This reverts commit ca1e002806.

app/models/card.rb

@@ -11,8 +11,6 @@ class Card < ApplicationRecord
 
   has_markdown :description
 
-  before_save :set_default_title
-
   scope :reverse_chronologically, -> { order created_at: :desc, id: :desc }
   scope :chronologically, -> { order created_at: :asc, id: :asc }
   scope :latest, -> { order updated_at: :desc, id: :desc }
@@ -27,12 +25,11 @@ class Card < ApplicationRecord
     end
   end
 
+  def title=(new_title)
+    self[:title] = new_title.presence || "Untitled"
+  end
+
   def cache_key
     [ super, collection.name ].compact.join("/")
   end
-
-  private
-    def set_default_title
-      self.title = "Untitled" if published? && title.blank?
-    end
 end

test/models/card_test.rb

@@ -120,12 +120,4 @@ class CardTest < ActiveSupport::TestCase
 
     assert_includes card.cache_key, ApplicationRecord.current_tenant, "cache key must always include the tenant"
   end
-
-  test "for published cards, it should set the default title 'Untitiled' when not provided" do
-    card = collections(:writebook).cards.create!
-    assert_nil card.title
-
-    card.publish
-    assert_equal "Untitled", card.reload.title
-  end
 end