Open log file with UTF-8 encoding

Specify encoding='utf-8' when opening the log file in append mode to ensure non-ASCII characters are written correctly and to avoid Unicode-related errors when writing log entries.

cli/main.py

@@ -948,7 +948,7 @@ def run_analysis():
             func(*args, **kwargs)
             timestamp, message_type, content = obj.messages[-1]
             content = content.replace("\n", " ")  # Replace newlines with spaces
-            with open(log_file, "a") as f:
+            with open(log_file, "a", encoding="utf-8") as f:
                 f.write(f"{timestamp} [{message_type}] {content}\n")
         return wrapper