Implement product variations, enhanced order workflow, mobile responsiveness, and product import system

## Product Variations System
- Add ProductVariation model with quantity-based pricing (1 for £10, 2 for £19, 3 for £25)
- Complete CRUD operations for product variations
- Enhanced ProductService to include variations in all queries
- Updated OrderItem to support ProductVariationId for variation-based orders
- Graceful error handling for duplicate quantity constraints
- Admin interface with variations management (Create/Edit/Delete)
- API endpoints for programmatic variation management

## Enhanced Order Workflow Management
- Redesigned OrderStatus enum with clear workflow states (Accept → Packing → Dispatched → Delivered)
- Added workflow tracking fields (AcceptedAt, PackingStartedAt, DispatchedAt, ExpectedDeliveryDate)
- User tracking for accountability (AcceptedByUser, PackedByUser, DispatchedByUser)
- Automatic delivery date calculation (dispatch date + working days, skips weekends)
- On Hold workflow for problem resolution with reason tracking
- Tab-based orders interface focused on workflow stages
- One-click workflow actions from list view

## Mobile-Responsive Design
- Responsive orders interface: tables on desktop, cards on mobile
- Touch-friendly buttons and spacing for mobile users
- Horizontal scrolling tabs with condensed labels on mobile
- Color-coded status borders for quick visual recognition
- Smart text switching based on screen size

## Product Import/Export System
- CSV import with product variations support
- Template download with examples
- Export existing products to CSV
- Detailed import results with success/error reporting
- Category name resolution (no need for GUIDs)
- Photo URLs import support

## Enhanced Dashboard
- Product variations count and metrics
- Stock alerts (low stock/out of stock warnings)
- Order workflow breakdown (pending, accepted, dispatched counts)
- Enhanced layout with more detailed information

## Technical Improvements
- Fixed form binding issues across all admin forms
- Removed external CDN dependencies for isolated deployment
- Bot Wizard form with auto-personality assignment
- Proper authentication scheme configuration (Cookie + JWT)
- Enhanced debug logging for troubleshooting

## Self-Contained Deployment
- All external CDN references replaced with local libraries
- Ready for air-gapped/isolated network deployment
- No external internet dependencies

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

LittleShop/Models/Order.cs

@@ -56,7 +56,26 @@ public class Order
     public DateTime UpdatedAt { get; set; } = DateTime.UtcNow;
     
     public DateTime? PaidAt { get; set; }
-    
+
+    // Workflow timestamps
+    public DateTime? AcceptedAt { get; set; }
+    public DateTime? PackingStartedAt { get; set; }
+    public DateTime? DispatchedAt { get; set; } // Replaces ShippedAt for clarity
+    public DateTime? ExpectedDeliveryDate { get; set; }
+    public DateTime? ActualDeliveryDate { get; set; }
+    public DateTime? OnHoldAt { get; set; }
+
+    // Workflow details
+    [StringLength(100)]
+    public string? AcceptedByUser { get; set; } // User who accepted the order
+    [StringLength(100)]
+    public string? PackedByUser { get; set; }   // User who packed the order
+    [StringLength(100)]
+    public string? DispatchedByUser { get; set; } // User who dispatched the order
+    [StringLength(500)]
+    public string? OnHoldReason { get; set; }   // Reason for putting on hold
+
+    // Legacy field (for backward compatibility)
     public DateTime? ShippedAt { get; set; }
     
     // Navigation properties

LittleShop/Models/OrderItem.cs

@@ -11,16 +11,19 @@ public class OrderItem
     public Guid OrderId { get; set; }
     
     public Guid ProductId { get; set; }
-    
+
+    public Guid? ProductVariationId { get; set; } // Nullable for backward compatibility
+
     public int Quantity { get; set; }
-    
+
     [Column(TypeName = "decimal(18,2)")]
     public decimal UnitPrice { get; set; }
-    
+
     [Column(TypeName = "decimal(18,2)")]
     public decimal TotalPrice { get; set; }
-    
+
     // Navigation properties
     public virtual Order Order { get; set; } = null!;
     public virtual Product Product { get; set; } = null!;
+    public virtual ProductVariation? ProductVariation { get; set; }
 }

LittleShop/Models/Product.cs

@@ -36,6 +36,7 @@ public class Product
     // Navigation properties
     public virtual Category Category { get; set; } = null!;
     public virtual ICollection<ProductPhoto> Photos { get; set; } = new List<ProductPhoto>();
+    public virtual ICollection<ProductVariation> Variations { get; set; } = new List<ProductVariation>();
     public virtual ICollection<OrderItem> OrderItems { get; set; } = new List<OrderItem>();
     public virtual ICollection<Review> Reviews { get; set; } = new List<Review>();
 }

LittleShop/Models/ProductVariation.cs

@@ -0,0 +1,38 @@
+using System.ComponentModel.DataAnnotations;
+using System.ComponentModel.DataAnnotations.Schema;
+
+namespace LittleShop.Models;
+
+public class ProductVariation
+{
+    [Key]
+    public Guid Id { get; set; }
+
+    public Guid ProductId { get; set; }
+
+    [Required]
+    [StringLength(100)]
+    public string Name { get; set; } = string.Empty; // e.g., "Single Item", "Twin Pack", "Triple Pack"
+
+    public string Description { get; set; } = string.Empty; // e.g., "Best value for 3 items"
+
+    public int Quantity { get; set; } // The quantity this variation represents (1, 2, 3, etc.)
+
+    [Column(TypeName = "decimal(18,2)")]
+    public decimal Price { get; set; } // The price for this quantity (£10, £19, £25)
+
+    [Column(TypeName = "decimal(18,2)")]
+    public decimal PricePerUnit { get; set; } // Calculated: Price / Quantity (for easy comparison)
+
+    public int SortOrder { get; set; } = 0; // For controlling display order
+
+    public bool IsActive { get; set; } = true;
+
+    public DateTime CreatedAt { get; set; } = DateTime.UtcNow;
+
+    public DateTime UpdatedAt { get; set; } = DateTime.UtcNow;
+
+    // Navigation properties
+    public virtual Product Product { get; set; } = null!;
+    public virtual ICollection<OrderItem> OrderItems { get; set; } = new List<OrderItem>();
+}