Dynamic ETD Offset Logic for Shopify Integration

User Story: As a Cin7 Omni user managing high-volume Shopify orders, I want the ability to set an "Estimated Time of Delivery" (ETD) offset (e.g., Created Date + X business days) in the Shopify connection settings, so that my fulfillment team and customers have accurate delivery expectations without manual intervention.

Current Limitation: Currently, the Shopify integration only allows for "Current Date" or "Created Date" to be mapped to the ETD field. This does not account for internal processing times, lead times, or warehouse handling periods.

Proposed Solution: Add a "Lead Time Offset" or "Offset Days" field in the Shopify Connection settings under the ETD mapping.

• Option A: Created Date + [X] days.
• Option B: Current Date + [X] days.
• Toggle: Option to exclude weekends (Business Days only).

Business Value:

• Automation: Reduces manual updates to Sales Orders after download.
• Accuracy: Syncs more realistic delivery dates to downstream systems and shipping labels.
• Scalability: Allows us to manage customer expectations automatically as order volume grows.