TST: JAX 0.7.0

[crusaderky]

Move the default Python version for backends to 3.13.
This is necessary for JAX, which has already dropped 3.10; others are expected to follow.
Test JAX 0.7.0 where possible.

Notable upgrades:

Platform: tests-backends:linux-64                                                   
  ~ C jax                                 0.6.0 pyhd8ed1ab_0                    ->  0.7.0 pyhd8ed1ab_0
  ~ C jaxlib                              0.6.0 cpu_py310hc96afab_0             ->  0.7.0 cpu_py313h9430eff_0
  ~ C python                              3.10.18 hd6af730_0_cpython            ->  3.13.7 h2b335a9_100_cp313
  ~ C scipy                               1.15.2 py310h1d65ade_0                ->  1.16.1 py313h11c21cd_1

Platform: tests-cuda:linux-64                                                       
  ~ C python                              3.10.18 hd6af730_0_cpython            ->  3.13.7 h2b335a9_100_cp313
  ~ C scipy                               1.15.2 py310h1d65ade_0                ->  1.16.1 py313h11c21cd_1

Platform: tests-backends-py310:linux-64  (new environment)
  + C jax                                 0.6.2 pyhd8ed1ab_0                        
  + C jaxlib                              0.6.2 cpu_py310h772e2ea_1                 
  + C python                              3.10.18 hd6af730_0_cpython                
  + C scipy                               1.15.2 py310h1d65ade_0                    

Platform: tests-cuda-py310:linux-64  (new environment)
  + C jax                                 0.6.0 pyhd8ed1ab_0                        
  + C jaxlib                              0.6.0 cuda126py310hec873cc_200            
  + C python                              3.10.18 hd6af730_0_cpython                
  + C scipy                               1.15.2 py310h1d65ade_0                    

[lucascolley]

thanks Guido!