Add save_cmdstan_config=1 to cmdstan call

Author: amas0

cmdstanpy/cmdstan_args.py

@@ -866,6 +866,7 @@ def compose_command(
                 cmd.append(f'init={self.inits[idx]}')
         cmd.append('output')
         cmd.append(f'file={csv_file}')
+        cmd.append('save_cmdstan_config=1')
         if diagnostic_file:
             cmd.append(f'diagnostic_file={diagnostic_file}')
         if profile_file: