save reports & logs under results_dir

tradingagents/default_config.py

@@ -2,6 +2,7 @@ import os
 
 DEFAULT_CONFIG = {
     "project_dir": os.path.abspath(os.path.join(os.path.dirname(__file__), ".")),
+    "results_dir": os.getenv("TRADINGAGENTS_RESULTS_DIR", "./results"),
     "data_dir": "/Users/yluo/Documents/Code/ScAI/FR1-data",
     "data_cache_dir": os.path.join(
         os.path.abspath(os.path.join(os.path.dirname(__file__), ".")),