Automatic inventory location linking

We’ve refined how inventory is handled during updates to make managing stock across locations smoother and less error-prone.

🔧 Improvements

• Automatic location linking – Connects inventory locations automatically when setting variants to streamline setup.
• Clearer validation – Shows specific errors when setting inventory on variants without inventory tracking enabled.
• Multilocation logic – Ignores “Variant Inventory Qty” when using multilocation inventory to avoid data conflicts.