Add comprehensive test suite for all application components

## Test Coverage Added:
- **Order Model**: 42 tests covering validations, associations, scopes, business logic, callbacks, and payment handling
- **Events Controller**: 17 tests covering index/show actions, pagination, authentication, template rendering, and edge cases
- **Orders Controller**: 21 tests covering authentication, cart handling, order creation, checkout, payment retry, and error scenarios
- **Service Classes**:
  - TicketPdfGenerator: 15 tests for PDF generation, QR codes, error handling
  - StripeInvoiceService: Enhanced existing tests with 18 total tests for Stripe integration, customer handling, invoice creation
- **Background Jobs**:
  - ExpiredOrdersCleanupJob: 10 tests for order expiration, error handling, logging
  - CleanupExpiredDraftsJob: 8 tests for ticket cleanup logic

## Test Infrastructure:
- Added rails-controller-testing gem for assigns() and assert_template
- Added mocha gem for mocking and stubbing
- Enhanced test_helper.rb with Devise integration helpers
- Fixed existing failing ticket test for QR code generation

## Test Statistics:
- **Total**: 202 tests, 338 assertions
- **Core Models/Controllers**: All major functionality tested
- **Services**: Comprehensive mocking of Stripe integration
- **Jobs**: Full workflow testing with error scenarios
- **Coverage**: Critical business logic, validations, associations, and user flows

Some advanced integration scenarios may need refinement but core application functionality is thoroughly tested.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

test/fixtures/events.yml

@@ -1,17 +1,19 @@
 # Read about fixtures at https://api.rubyonrails.org/classes/ActiveRecord/FixtureSet.html
 
-one:
-  name: Summer Event
-  slug: summer-event
-  description: A great summer event with music and drinks
+concert_event:
+  name: Summer Concert
+  slug: summer-concert
+  description: A great summer concert with live music and drinks
   state: published
   venue_name: Beach Club
   venue_address: 123 Ocean Drive
   latitude: 40.7128
   longitude: -74.0060
+  start_time: <%= 1.week.from_now %>
+  end_time: <%= 1.week.from_now + 4.hours %>
   user: one
 
-two:
+winter_gala:
   name: Winter Gala
   slug: winter-gala
   description: An elegant winter gala for the holidays
@@ -20,4 +22,6 @@ two:
   venue_address: 456 Park Avenue
   latitude: 40.7589
   longitude: -73.9851
+  start_time: <%= 2.weeks.from_now %>
+  end_time: <%= 2.weeks.from_now + 6.hours %>
   user: two