feat: Implement promoter payout system for event revenue processing

- Add Payout model with associations to User and Event
- Create payout requests for completed events with proper earnings calculation
- Exclude refunded tickets from payout calculations
- Add promoter dashboard views for managing payouts
- Implement admin interface for processing payouts
- Integrate with Stripe for actual payment processing
- Add comprehensive tests for payout functionality

Co-authored-by: Qwen-Coder <qwen-coder@alibabacloud.com>

app/models/user.rb

@@ -24,6 +24,7 @@ class User < ApplicationRecord
   has_many :tickets, dependent: :destroy
   has_many :orders, dependent: :destroy
   has_many :earnings, dependent: :destroy
+  has_many :payouts, dependent: :destroy
 
   # Validations - allow reasonable name lengths
   validates :last_name,   length: { minimum: 2, maximum: 50, allow_blank: true }