Conform to the Array return annotations from #2206

Narrow the new classes' returns from ArrayLike to Array, take Optional keys
in sample with the accompanying assert, cast constraint bounds to NumLike,
and declare _support at class level — matching what #2206 applied to the
existing truncated classes.

The generic test_output_is_array added by that PR also caught a broadcasting
bug in the bisection helpers: promote_shapes can leave low and high at size-1
dims while the cdf carries the full batch shape, so the fori_loop carry changed
shape mid-loop for batched parameters. The helpers now take the target shape
explicitly, broadcast from the quantile shape and the distribution's batch
shape.

Author: deeb01