fix: remove isatty guard in _ensure_utf8_console (#95) (#101)

The isatty() check skipped UTF-8 wrapping when agent-reach was called
as a subprocess by AI agents (non-TTY). On Windows with GBK encoding,
any remaining non-ASCII chars would crash with UnicodeEncodeError.

Now UTF-8 wrapping applies in all environments on Windows.

Closes #95

Co-authored-by: Panniantong <panniantong@users.noreply.github.com>

agent_reach/cli.py

@@ -25,8 +25,6 @@ def _ensure_utf8_console():
     # Avoid interfering with pytest/captured streams.
     if os.environ.get("PYTEST_CURRENT_TEST"):
         return
-    if not getattr(sys.stdout, "isatty", lambda: False)():
-        return
     try:
         import io
         if hasattr(sys.stdout, "buffer"):