feat: add supplier payment and allocation models, API, and frontend components

- Created `SupplierPayment` and `SupplierPaymentGRN` models for managing supplier payments and their allocations.
- Implemented API endpoints for listing and creating supplier payments.
- Developed frontend components for displaying and recording supplier payments, including a dialog for payment creation.
- Integrated GRN allocations into the payment creation process, ensuring total allocations match the payment amount.
- Added pagination and loading states for the payments list.

Distribution/Data/AppDBContext.cs

@@ -69,6 +69,8 @@ public class AppDBContext(DbContextOptions<AppDBContext> options) : DbContext(op
     public DbSet<ChequeBook> ChequeBooks { get; set; }
     public DbSet<ChequePage> ChequePages { get; set; }
     public DbSet<ReceivedCheque> ReceivedCheques { get; set; }
+    public DbSet<SupplierPayment> SupplierPayments { get; set; }
+    public DbSet<SupplierPaymentGRN> SupplierPaymentGRNs { get; set; }
 
     protected override void OnModelCreating(ModelBuilder modelBuilder)
     {
@@ -665,6 +667,46 @@ public class AppDBContext(DbContextOptions<AppDBContext> options) : DbContext(op
             .OnDelete(DeleteBehavior.Restrict)
             .IsRequired(false);
 
+        // --- SupplierPayment ---
+
+        modelBuilder.Entity<SupplierPayment>()
+            .HasOne(p => p.Supplier)
+            .WithMany()
+            .HasForeignKey(p => p.FK_SupplierId)
+            .OnDelete(DeleteBehavior.Restrict);
+
+        modelBuilder.Entity<SupplierPayment>()
+            .HasOne(p => p.BankAccount)
+            .WithMany()
+            .HasForeignKey(p => p.FK_BankAccountId)
+            .OnDelete(DeleteBehavior.Restrict)
+            .IsRequired(false);
+
+        modelBuilder.Entity<SupplierPayment>()
+            .HasOne(p => p.ChequePage)
+            .WithMany()
+            .HasForeignKey(p => p.FK_ChequePageId)
+            .OnDelete(DeleteBehavior.Restrict)
+            .IsRequired(false);
+
+        modelBuilder.Entity<SupplierPayment>()
+            .Property(p => p.Amount).HasPrecision(18, 2);
+
+        modelBuilder.Entity<SupplierPaymentGRN>()
+            .HasOne(a => a.SupplierPayment)
+            .WithMany(p => p.Allocations)
+            .HasForeignKey(a => a.FK_SupplierPaymentId)
+            .OnDelete(DeleteBehavior.Cascade);
+
+        modelBuilder.Entity<SupplierPaymentGRN>()
+            .HasOne(a => a.GoodsReceipt)
+            .WithMany()
+            .HasForeignKey(a => a.FK_GoodsReceiptId)
+            .OnDelete(DeleteBehavior.Restrict);
+
+        modelBuilder.Entity<SupplierPaymentGRN>()
+            .HasIndex(a => a.FK_GoodsReceiptId);
+
         Seed.RoleAndPermissionSeed.Apply(modelBuilder);
         Seed.MasterDataSeed.Apply(modelBuilder);
         Seed.OperationsDataSeed.Apply(modelBuilder);