Pin text I/O to UTF-8 and fail CI on locale-dependent reads/writes (#3296)

Co-authored-by: ShuQingDollarVoyager <57471784+ShuQingDollarVoyager@users.noreply.github.com>
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>

examples/clients/simple-chatbot/mcp_simple_chatbot/main.py

@@ -44,7 +44,7 @@ class Configuration:
             FileNotFoundError: If configuration file doesn't exist.
             JSONDecodeError: If configuration file is invalid JSON.
         """
-        with open(file_path, "r") as f:
+        with open(file_path, encoding="utf-8") as f:
             return json.load(f)
 
     @property