feat: Implement complete ticket purchasing flow with new TicketsController

- Create new TicketsController with actions for name collection, creation, and checkout
- Add dedicated ticket views (new.html.erb, checkout.html.erb, show.html.erb)
- Update ticket_selection_controller.js to handle form submission via AJAX
- Add store_cart endpoint in EventsController for session-based cart management
- Update routes to support new ticket flow: /tickets/new, /create, /checkout
- Fix attribute name consistency across views (title→name, starts_at→start_time)
- Add Stripe checkout integration with proper error handling
- Remove deprecated collect_names flow in favor of streamlined approach

The flow is now: Event selection → AJAX cart storage → Name collection → Checkout → Payment

app/models/ticket.rb

@@ -1,17 +1,17 @@
 class Ticket < ApplicationRecord
-  # Associations
+  # === Associations ===
   belongs_to :user
   belongs_to :ticket_type
   has_one :event, through: :ticket_type
 
-  # Validations
+  # === Validations ===
   validates :qr_code, presence: true, uniqueness: true
   validates :user_id, presence: true
   validates :ticket_type_id, presence: true
   validates :price_cents, presence: true, numericality: { greater_than: 0 }
-  validates :status, presence: true, inclusion: { in: %w[active used expired refunded] }
-  validates :first_name, presence: true, if: :requires_names?
-  validates :last_name, presence: true, if: :requires_names?
+  validates :status, presence: true, inclusion: { in: %w[draft active used expired refunded] }
+  validates :first_name, presence: true
+  validates :last_name, presence: true
 
   before_validation :set_price_from_ticket_type, on: :create
   before_validation :generate_qr_code, on: :create
@@ -26,11 +26,6 @@ class Ticket < ApplicationRecord
     price_cents / 100.0
   end
 
-  # Check if names are required for this ticket type
-  def requires_names?
-    ticket_type&.requires_id
-  end
-
   private
 
   def set_price_from_ticket_type
@@ -40,7 +35,7 @@ class Ticket < ApplicationRecord
 
   def generate_qr_code
     return if qr_code.present?
-    
+
     loop do
       self.qr_code = SecureRandom.uuid
       break unless Ticket.exists?(qr_code: qr_code)