Fix Place Order API Flow and Improve Payment Validation

[rohansingh754]

Improves the Place Order API by restructuring the order creation flow and enhancing payment validation. The changes ensure better reliability, extensibility, and consistency across the order and invoice processes.

Key Changes

• Refactored the order creation flow to validate payment before creating the order
• Introduced a new event hook to allow custom packages to manage or extend the order flow
• Updated the invoice creation flow for better separation of responsibilities
• Removed payment validation logic from the invoice creation method

Benefits

• Prevents orders from being created when payment validation fails
• Provides a more flexible and extensible order flow for custom integrations
• Improves code maintainability and clarity
• Reduces the risk of duplicate or misplaced payment validation

Testing

• Verified successful order creation with valid payments
• Confirmed that orders are not created when payment validation fails
• Tested invoice generation after successful order placement

[rohansingh754]

Issue: #574