refactor(bootstrap): migrate payment items to seed file

Lifts ImportPaymentItems out of GlobalsImporter into a dedicated
PaymentItemImporter driven by Data/seeds/payment-items.json. Wired
into Program.cs and SVSimTestFactory.SeedGlobalsAsync after
PracticeOpponentImporter. Drops the prod-capture file in favor of
the extractor pipeline.

Canonical 4-test suite (basic, idempotent, leave-untouched, skip-zero)
keeps the dict-in-sync upsert pattern Task 2 established.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

SVSim.UnitTests/Importers/PaymentItemImporterTests.cs

@@ -0,0 +1,87 @@
+using Microsoft.EntityFrameworkCore;
+using Microsoft.Extensions.DependencyInjection;
+using SVSim.Bootstrap.Importers;
+using SVSim.Database;
+using SVSim.UnitTests.Infrastructure;
+
+namespace SVSim.UnitTests.Importers;
+
+public class PaymentItemImporterTests
+{
+    private static string SeedDir => Path.Combine(AppContext.BaseDirectory, "Data", "seeds");
+
+    [Test]
+    public async Task Imports_items_from_seed_file()
+    {
+        using var factory = new SVSimTestFactory();
+        using var scope = factory.Services.CreateScope();
+        var db = scope.ServiceProvider.GetRequiredService<SVSimDbContext>();
+
+        await new PaymentItemImporter().ImportAsync(db, SeedDir);
+
+        var items = await db.PaymentItems.OrderBy(p => p.Id).ToListAsync();
+        Assert.That(items.Count, Is.GreaterThan(0), "seed file must contain items");
+        Assert.That(items.All(i => i.Price >= 0m), Is.True);
+    }
+
+    [Test]
+    public async Task Is_idempotent_on_rerun()
+    {
+        using var factory = new SVSimTestFactory();
+        using var scope = factory.Services.CreateScope();
+        var db = scope.ServiceProvider.GetRequiredService<SVSimDbContext>();
+
+        await new PaymentItemImporter().ImportAsync(db, SeedDir);
+        int before = await db.PaymentItems.CountAsync();
+        await new PaymentItemImporter().ImportAsync(db, SeedDir);
+        int after = await db.PaymentItems.CountAsync();
+
+        Assert.That(after, Is.EqualTo(before));
+    }
+
+    [Test]
+    public async Task Leaves_existing_rows_untouched_when_missing_from_seed()
+    {
+        using var factory = new SVSimTestFactory();
+        using var scope = factory.Services.CreateScope();
+        var db = scope.ServiceProvider.GetRequiredService<SVSimDbContext>();
+
+        const int legacyId = 99999;
+        db.PaymentItems.Add(new SVSim.Database.Models.PaymentItemEntry
+        {
+            Id = legacyId,
+            ProductId = 0,
+            Name = "legacy",
+            Price = 0m,
+        });
+        await db.SaveChangesAsync();
+
+        await new PaymentItemImporter().ImportAsync(db, SeedDir);
+
+        var legacy = await db.PaymentItems.FindAsync(legacyId);
+        Assert.That(legacy, Is.Not.Null, "seed-missing row must be left intact");
+        Assert.That(legacy!.Name, Is.EqualTo("legacy"));
+    }
+
+    [Test]
+    public async Task Skips_rows_with_zero_record_id()
+    {
+        using var factory = new SVSimTestFactory();
+        using var scope = factory.Services.CreateScope();
+        var db = scope.ServiceProvider.GetRequiredService<SVSimDbContext>();
+
+        string tmp = Path.Combine(Path.GetTempPath(), $"seed-{Guid.NewGuid()}");
+        Directory.CreateDirectory(tmp);
+        try
+        {
+            File.WriteAllText(Path.Combine(tmp, "payment-items.json"),
+                "[{\"record_id\":0,\"product_id\":1,\"name\":\"junk\",\"price\":\"0\"}]");
+
+            await new PaymentItemImporter().ImportAsync(db, tmp);
+
+            int count = await db.PaymentItems.CountAsync();
+            Assert.That(count, Is.EqualTo(0), "rows with record_id=0 must not be inserted");
+        }
+        finally { Directory.Delete(tmp, true); }
+    }
+}