feat: initial project setup

- Add .NET 8 backend with Clean Architecture
- Add React + Vite + TypeScript frontend
- Implement authentication with JWT
- Implement Azure Blob Storage client
- Implement OCR integration
- Implement supplier matching service
- Implement voucher generation
- Implement Fortnox provider
- Add unit and integration tests
- Add Docker Compose configuration

backend/src/InvoiceMaster.Infrastructure/Data/Configurations/SupplierCacheConfiguration.cs

@@ -0,0 +1,66 @@
+using InvoiceMaster.Core.Entities;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Metadata.Builders;
+
+namespace InvoiceMaster.Infrastructure.Data.Configurations;
+
+public class SupplierCacheConfiguration : IEntityTypeConfiguration<SupplierCache>
+{
+    public void Configure(EntityTypeBuilder<SupplierCache> builder)
+    {
+        builder.ToTable("supplier_cache");
+        
+        builder.HasKey(e => e.Id);
+        
+        builder.Property(e => e.SupplierNumber)
+            .IsRequired()
+            .HasMaxLength(50);
+            
+        builder.Property(e => e.Name)
+            .IsRequired()
+            .HasMaxLength(255);
+            
+        builder.Property(e => e.OrganisationNumber)
+            .HasMaxLength(20);
+            
+        builder.Property(e => e.Address1)
+            .HasMaxLength(255);
+            
+        builder.Property(e => e.Address2)
+            .HasMaxLength(255);
+            
+        builder.Property(e => e.Postcode)
+            .HasMaxLength(20);
+            
+        builder.Property(e => e.City)
+            .HasMaxLength(100);
+            
+        builder.Property(e => e.Country)
+            .HasMaxLength(100);
+            
+        builder.Property(e => e.Phone)
+            .HasMaxLength(50);
+            
+        builder.Property(e => e.Email)
+            .HasMaxLength(255);
+            
+        builder.Property(e => e.BankgiroNumber)
+            .HasMaxLength(50);
+            
+        builder.Property(e => e.PlusgiroNumber)
+            .HasMaxLength(50);
+            
+        builder.HasIndex(e => new { e.ConnectionId, e.SupplierNumber })
+            .IsUnique();
+            
+        builder.HasIndex(e => e.ConnectionId);
+        builder.HasIndex(e => e.OrganisationNumber);
+        builder.HasIndex(e => e.Name);
+        builder.HasIndex(e => e.ExpiresAt);
+        
+        builder.HasOne(e => e.Connection)
+            .WithMany()
+            .HasForeignKey(e => e.ConnectionId)
+            .OnDelete(DeleteBehavior.Cascade);
+    }
+}