feat: port GPU code to CUDA 13 and enable GPU computation

Major changes:
   - Update makefile.inc for CUDA 13.1 with sm_89 architecture (RTX 4050)
   - Replace deprecated cudaThreadSynchronize() with cudaDeviceSynchronize()
   - Add CUDA_SAFE_CALL macro for CUDA 13 compatibility
   - Fix duplicate function definitions (compare_result_gpu, SHStep)
   - Fix syntax error in bssn_step_gpu.C
   - Enable GPU calculation in AMSS_NCKU_Input.py
   - Successfully build ABEGPU executable

AMSS_NCKU_source/bssn_gpu.h

@@ -4,6 +4,17 @@
 #include "bssn_macro.h"
 #include "macrodef.fh"
 
+// CUDA error checking macro for CUDA 13 compatibility
+#define CUDA_SAFE_CALL(call) \
+    do { \
+        cudaError_t err = call; \
+        if (err != cudaSuccess) { \
+            fprintf(stderr, "CUDA error in %s:%d: %s\n", __FILE__, __LINE__, \
+                    cudaGetErrorString(err)); \
+            exit(EXIT_FAILURE); \
+        } \
+    } while(0)
+
 #define DEVICE_ID 0
 // #define DEVICE_ID_BY_MPI_RANK
 #define GRID_DIM 256