refactor: move index definitions to create migrations for tickets and ticket_types

db/migrate/20250823171354_create_tickets.rb

@@ -2,8 +2,16 @@ class CreateTickets < ActiveRecord::Migration[8.0]
   def change
     create_table :tickets do |t|
       t.string :qr_code
+      t.integer :price_cents
+      t.string :status, default: 'active'
+      t.references :user, null: false, foreign_key: true
+      t.references :ticket_type, null: false, foreign_key: true
 
       t.timestamps
     end
+
+    add_index :tickets, :qr_code, unique: true
+    add_index :tickets, :user_id unless index_exists?(:tickets, :user_id)
+    add_index :tickets, :ticket_type_id unless index_exists?(:tickets, :ticket_type_id)
   end
 end