ShadowverseTranslationMiddleware throws InvalidOperationException when
a Unity client posts an encrypted msgpack body to an action with zero
[FromBody] parameters — it has no target type for the deserializer.
Tests pass because they post JSON directly with no UnityPlayer UA and
the middleware short-circuits. Same defect already fixed on /replay/info
in 216dcab; this catches up the friend system shipped 2026-06-09.
Fixed actions: info, receive_apply_info, send_apply_info,
played_together_info, reject_apply_all, cancel_apply_all.
Tests updated to post the BaseRequest auth fields so [ApiController]
model validation passes (BaseRequest.ViewerId is non-nullable string).
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>