fix: isolate subprocess stdin and decouple startup to prevent MCP stdio deadlocks

- Set stdin=subprocess.DEVNULL across runtime, client, and utility subprocess calls to avoid hijacking the parent process's stdin.
- Run awake service initialization asynchronously on a daemon thread in MCP server startup.
- Redirect logger header printing to stderr to ensure stdio JSON-RPC purity.
- Add unit and lifecycle tests for MCP stdio protocol handshake and stdin isolation.

artemis/utils/logger.py

@@ -168,9 +168,9 @@ class ArtemisLogger:
         colored_separator = f"{Fore.CYAN}{separator}{Style.RESET_ALL}"
         colored_message = f"{Fore.CYAN}{message}{Style.RESET_ALL}"
 
-        print(colored_separator)
-        print(colored_message)
-        print(colored_separator)
+        print(colored_separator, file=sys.stderr)
+        print(colored_message, file=sys.stderr)
+        print(colored_separator, file=sys.stderr)
         self.logger.info(f"\n{separator}\n{message}\n{separator}")