feat: drop QuantityOnHand column and StockTransactions table

Final step of removing inventory quantity tracking - see
docs/superpowers/specs/2026-08-01-remove-inventory-quantity-tracking-design.md.
Destructive to any existing on-hand/transaction data; confirmed
acceptable since nothing read it automatically.

CutList.Web/Migrations/ApplicationDbContextModelSnapshot.cs

@@ -325,9 +325,6 @@ namespace CutList.Web.Migrations
                         .HasMaxLength(255)
                         .HasColumnType("nvarchar(255)");
 
-                    b.Property<int>("QuantityOnHand")
-                        .HasColumnType("int");
-
                     b.Property<DateTime?>("UpdatedAt")
                         .HasColumnType("datetime2");
 
@@ -339,44 +336,6 @@ namespace CutList.Web.Migrations
                     b.ToTable("StockItems");
                 });
 
-            modelBuilder.Entity("CutList.Web.Data.Entities.StockTransaction", b =>
-                {
-                    b.Property<int>("Id")
-                        .ValueGeneratedOnAdd()
-                        .HasColumnType("int");
-
-                    SqlServerPropertyBuilderExtensions.UseIdentityColumn(b.Property<int>("Id"));
-
-                    b.Property<DateTime>("CreatedAt")
-                        .ValueGeneratedOnAdd()
-                        .HasColumnType("datetime2")
-                        .HasDefaultValueSql("GETUTCDATE()");
-
-                    b.Property<int?>("JobId")
-                        .HasColumnType("int");
-
-                    b.Property<string>("Notes")
-                        .HasMaxLength(500)
-                        .HasColumnType("nvarchar(500)");
-
-                    b.Property<int>("Quantity")
-                        .HasColumnType("int");
-
-                    b.Property<int>("StockItemId")
-                        .HasColumnType("int");
-
-                    b.Property<int>("Type")
-                        .HasColumnType("int");
-
-                    b.HasKey("Id");
-
-                    b.HasIndex("JobId");
-
-                    b.HasIndex("StockItemId");
-
-                    b.ToTable("StockTransactions");
-                });
-
             modelBuilder.Entity("CutList.Web.Data.Entities.AngleDimensions", b =>
                 {
                     b.HasBaseType("CutList.Web.Data.Entities.MaterialDimensions");
@@ -632,24 +591,6 @@ namespace CutList.Web.Migrations
                     b.Navigation("Material");
                 });
 
-            modelBuilder.Entity("CutList.Web.Data.Entities.StockTransaction", b =>
-                {
-                    b.HasOne("CutList.Web.Data.Entities.Job", "Job")
-                        .WithMany()
-                        .HasForeignKey("JobId")
-                        .OnDelete(DeleteBehavior.SetNull);
-
-                    b.HasOne("CutList.Web.Data.Entities.StockItem", "StockItem")
-                        .WithMany("Transactions")
-                        .HasForeignKey("StockItemId")
-                        .OnDelete(DeleteBehavior.Cascade)
-                        .IsRequired();
-
-                    b.Navigation("Job");
-
-                    b.Navigation("StockItem");
-                });
-
             modelBuilder.Entity("CutList.Web.Data.Entities.CuttingTool", b =>
                 {
                     b.Navigation("Jobs");
@@ -670,11 +611,6 @@ namespace CutList.Web.Migrations
 
                     b.Navigation("StockItems");
                 });
-
-            modelBuilder.Entity("CutList.Web.Data.Entities.StockItem", b =>
-                {
-                    b.Navigation("Transactions");
-                });
 #pragma warning restore 612, 618
         }
     }