[JAX] Don't expand complex all-reduce ops into real/complex pairs. [XLA:CPU] Implement complex all-reductions for sum and product.
[JAX] Don't expand complex all-reduce ops into real/complex pairs.
[XLA:CPU] Implement complex all-reductions for sum and product.

Fixes https://github.com/google/jax/issues/11133 by making XLA implement the all-reduction whenever we build one, not just the one path on which we happened to have a workaround.

PiperOrigin-RevId: 455687275

google/jax,google/jax,google/jax,google/jax