Add loss function coverage to slow reconstruction tests

Use poisson_nll in test_near_field_ptycho and intensity_mse in
test_Adam_gold_balls to exercise these loss paths end-to-end.
Thresholds left as-is pending re-running on a GPU machine.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

tests/models/test_fancy_ptycho.py

@@ -138,7 +138,11 @@ def test_near_field_ptycho(near_field_ptycho_cxi, reconstruction_device, show_pl
         n_modes=1,
         near_field=True,
         propagation_distance=3.65e-3, # 3.65 downstream from focus
+<<<<<<< HEAD
         panel_plot_mode=False, # test without panel plot mode
+=======
+        loss='poisson_nll',
+>>>>>>> f0f1577 (Add loss function coverage to slow reconstruction tests)
     )
 
     print('Running reconstruction on provided reconstruction_device,',

tests/test_reconstructors.py

@@ -38,7 +38,11 @@ def test_Adam_gold_balls(gold_ball_cxi, reconstruction_device, show_plot):
         propagation_distance=2e-6,
         units='um',
         probe_fourier_crop=pad,
+<<<<<<< HEAD
         panel_plot_mode=False, # At least one check without panel plot mode
+=======
+        loss='intensity_mse',#NOTE: Only to check that it works.
+>>>>>>> f0f1577 (Add loss function coverage to slow reconstruction tests)
     )
 
     model.translation_offsets.data += 0.7 * \