sar3d: GPU port of the notebook with four views

The sar3d processor is rewritten as a checked port of Multi_antenna_3D_clean_v1.ipynb:
NVRTC kernels, timing from the trace stamps, notebook parameter names and one cubic
SAR_VOXEL_M. It adds front, side, top and 3D views, drops gpr_cpp and the parity tools,
and the GUI speed now applies only while the socket speed is ignored.

run_config_examples/run_config_replay_vna.example.json

@@ -178,21 +178,12 @@
         "speed_m_s": 0.854,
         "ignore_socket_speed_enabled": true,
         "look_angle_deg": 6.0,
-        "direction_sign": 1.0,
-        "apply_freq_phase_correction": true,
         "frame_radius": 6,
-        "edge_frame_weight": 0.75,
-        "pitch_deg": 6.0,
-        "center_depth_m": 5.6,
-        "half_width_x_m": 1.8,
-        "half_width_y_m": 1.0,
-        "half_width_z_m": 1.8,
-        "grid_nx": 150,
-        "grid_ny": 120,
-        "grid_nz": 160,
+        "voxel_m": 0.02,
+        "bp_ground_depth_m": 1.25,
+        "comp_range_power": 0.3,
         "use_compensation": true,
-        "normalize_pairs": true,
-        "bottom_view_deg": 0.0
+        "normalize_each_frame": true
       }
     },
     "preprocess_dialog": {