Add notifications of severed relationships (#27511)

db/migrate/20240312100644_create_relationship_severance_events.rb

@@ -0,0 +1,15 @@
+# frozen_string_literal: true
+
+class CreateRelationshipSeveranceEvents < ActiveRecord::Migration[7.0]
+  def change
+    create_table :relationship_severance_events do |t|
+      t.integer :type, null: false
+      t.string :target_name, null: false
+      t.boolean :purged, null: false, default: false
+
+      t.timestamps
+
+      t.index [:type, :target_name]
+    end
+  end
+end