Evergreen farms (pos)

- Added six transactional emails for cancellations and refunds, with duplicate-send prevention, event tracking, and failure handling that never blocks the cancellation or refund process.
- Integrated refund success and failure notifications through Stripe webhooks and clarified the roles of `base.mail.js` and `notifyUsers.js`.
- Added cancellation alerts for Pickers, Packers, Droppers, and Managers, with clear “On Hold” and “Cancelled: Do Not Ship” banners on warehouse order pages.
- Fixed packing workflows to skip held or cancelled items, allowing the remaining order to proceed without interruption.
- Automatically closed completed floor tasks, voided shipping labels covering only cancelled items, and introduced return-to-shelf tasks with dashboard panels.
- Improved cancellation queues and approval dialogs by displaying each item's warehouse, current stage, and required action.
- Fixed stale-order errors through live order validation and safe retries, improved diagnostic logging, and corrected misleading pending-request messages.
- Simplified cancellation and refund messaging, added dismissible error banners and quick-select blocking reasons, and cleaned up refund forms and request history.
- Added a Cancellations & Refunds tab to Customer Details, Cancelled and Refunded order badges, and refund summary cards to the Sales and main Dashboards, respecting the selected date filter.
- Identified six outstanding warehouse security and workflow issues involving role validation, tracking numbers, skippable steps, search safety, atomic packing, and mock Picker data.
- Identified the default-warehouse fallback causing incorrect warehouse assignments; awaiting a decision between an Unassigned queue and a flagged default warehouse.
- Reduced repeated `access` calls and added diagnostic logging to help identify the underlying trigger.