Core library improvement

[lampajr]

As raised here:

• check if we can get away without ZeroIfNil but dereference the pointer (I did not found a way at the time, since this snippet prints the address for instance:

	x := 123
	y := &x
	fmt.Printf("%v", y)

but we can keep the ZeroIfNil, this is just a minor check worth of doing

• Check if we can refactor some of the methods, similarly to how it was done leveraging func mapTo[S getTypeIder, T any](s S, id int64, convFn func(S) (*T, error)) (*T, error)