Without network a signaling context is never prepared. Like
ActivateSession, ActivateUser and GetConnectionInfo,
sceNpSessionSignalingRequestPrepare returns 0x80552D06 (UNAVAILABLE)
and writes no request id. sceNpSessionSignalingGetLocalNetInfo no
longer throws: it returns 0x80552D06 and leaves the info unchanged, as
libSceNetCtl reports neither an address nor NAT info offline. A null
request id or info returns 0x80552D02, as a null context id does in
CreateContext2. GetConnectionStatus still throws.
The new guest_np_session_signaling test checks the error codes and
that failed calls leave the request id and info unchanged; it is
registered in a new libSceNpSessionSignaling CMakeLists.txt.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>