fix(transaction): preserve primary failures

Keep action and commit exceptions when rollback fails; clear owned transaction state and cover the lifecycle with SQLite tests.

Ref: IT-1588

HrynCo.DAL.EF.Tests/TestUnitOfWork.cs

@@ -0,0 +1,6 @@
+namespace HrynCo.DAL.EF.Tests;
+
+using HrynCo.DAL.EF.Core;
+using Microsoft.EntityFrameworkCore;
+
+internal sealed class TestUnitOfWork(DbContext context) : EfUnitOfWork<DbContext>(context);