Considering either re-exporting jiff or removing Span from public API

[chungwong]

At the moment jiff::Span is used in a few places, see the In Parameters tab,

Because of the above and also the slow adoption of jiff(I only cargo added it because underway is using it), one has to pay extra attention to the version cargo is adding.

error[E0308]: mismatched types
    --> src/lib.rs:27:45
     |
  27 |     underway::queue::run_deletion_every(db, 1.hour()).await;
     |     -----------------------------------     ^^^^^^^^ expected `jiff::span::Span`, found `Span`
     |     |
     |     arguments to this function are incorrect
     |
note: two different versions of crate `jiff` are being used; two types coming from two different versions of the same crate are different types even if they look the same
    --> /home/chung/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/jiff-0.2.17/src/span.rs:711:1
     |
 711 | pub struct Span {
     | ^^^^^^^^^^^^^^^ this is the found type `Span`
     |
    ::: /home/chung/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/jiff-0.1.29/src/span.rs:686:1
     |
 686 | pub struct Span {
     | ^^^^^^^^^^^^^^^ this is the expected type `jiff::span::Span`

From what I can see, Span is purely for convenience and at the end it is converted to std::time::Duration anyway.
I am wondering if it is reasonable to either

1. just re-export jiff or jiff::Span?
2. just remove Span completely and accept Duration instead, I know it is a bit annoying to make a Duration.