fix: socket assertion crashes and add Nex service stub

- Replace socket option assertion failures with proper error returns
- Add WSAENOPROTOOPT/ENOPROTOOPT error handling
- Fix LINGER and option value size validation
- Add Network::Errno::OTHER translation
- Implement basic Nex service stub for error code 2306-0520

Fixes crashes in Minecraft and other games when encountering unsupported
socket operations or attempting to use Nintendo's online services.

Signed-off-by: Zephyron <zephyron@citron-emu.org>

src/core/internal_network/network.cpp

@@ -158,6 +158,8 @@ Errno TranslateNativeError(int e, CallType call_type = CallType::Other) {
         return Errno::TIMEDOUT;
     case WSAEINPROGRESS:
         return Errno::INPROGRESS;
+    case WSAENOPROTOOPT:
+        return Errno::INVAL;
     default:
         UNIMPLEMENTED_MSG("Unimplemented errno={}", e);
         return Errno::OTHER;
@@ -297,6 +299,8 @@ Errno TranslateNativeError(int e, CallType call_type = CallType::Other) {
         return Errno::TIMEDOUT;
     case EINPROGRESS:
         return Errno::INPROGRESS;
+    case ENOPROTOOPT:
+        return Errno::INVAL;
     default:
         UNIMPLEMENTED_MSG("Unimplemented errno={} ({})", e, strerror(e));
         return Errno::OTHER;