Implement auto-cancel unpaid orders feature with settings

[Shreyansh284]

Fixes #8120

📌 Summary

Implemented automatic cancellation of unpaid orders (Payment Status: Pending) after a configurable time
period using a scheduled task.

⚙️ Features Added

• Added setting to enable/disable auto-cancellation of unpaid orders (disabled by default)
• Configurable delay (in minutes) after which unpaid orders are cancelled (default: 600 minutes)
• Ability to exclude specific payment methods from auto-cancellation via multi-select dropdown
• Option to restore order items back to the shopping cart after cancellation (disabled by default)

🛠️ Technical Implementation

• Extended OrderSettings with new configuration properties
• Added admin UI controls under Configuration → Settings → Order
• Implemented CancelUnpaidOrdersTask using IScheduleTask
• Efficiently fetches only eligible orders (PaymentStatus.Pending & older than configured time)
• Uses IOrderService for order cancellation
• Uses IPaymentPluginManager to dynamically load payment methods for dropdown
• Stores ignored payment methods as comma-separated system names (nopCommerce standard)

🧪 Testing

• Verified scheduled task cancels eligible unpaid orders correctly
• Confirmed excluded payment methods are not affected
• Validated optional cart restoration functionality
• Tested settings persistence and UI behavior

⚠️ Notes

• Feature is disabled by default to avoid unintended behavior
• No breaking changes introduced
• Follows existing nopCommerce coding standards and patterns

[AndreiMaz]

Thanks a lot! But we've also already implemented it. Here is the branch (will be merged soon) - https://github.com/nopSolutions/nopCommerce/tree/issue-8120-auto-cancel-unpaid-orders

[exileDev]

Thank you for your contribution, but we have already fixed this, as mentioned above.