WPF DI with DbContext per form

Trying to figure out how to keep class methods clean, follow EF's guidance of short-lived DbContexts, and use DI in WPF. Issue I'm having is implementing transactions with DI. I'm trying to figure out what the best way of handling this:

public class Repository : IRepository
{
    public Repository(MyDbContext dataContext) { /* blah */ }

    public void Add(BLLEntity entity) { /* blah */ }

    public void GetById(int id) { /* return entity */ }
}

public class NonTransactionalAppService
{
    public AppService(IRepository repo) { /* blah */ }

    public AddNewAccount(Account account)  // Issue: Not transactional
    {
        // do some stuff....
        repo.Add(account);
    }
}

public class TransactionalAppService
{
    public TransactionalAppService(IRepositoryFactory repoFactory, DbContextFactory factory) { /* blah */ }

    public AddNewAccount(Account account)  // Issue: Transactional, but odd?? And requires me to create the repositories with every call.
    {
        using (var db = factory.Create()
        {
            IRepo repo = repoFactory.Create(db);
            repo.Add(account);
        }
    }
}

So how do I handle transactions, keep DI for better unit-testing, and inject only what's needed without injecting factories everywhere?

This is for a desktop WPF app and I do not want to use a DI framework.

EF has guidance to use one DbContext per form, but how would I handle that with the Composition Root? I would assume I would need some type of FormFactory that would create a form and inject all the required dependencies to include the DbContext.