gameserver: consume Cycle's extra header bit -> bunches align (NMT_Hello parses)

Bit-decoded real client packets: the header is 65 bits (not stock UE 4.27's 64).
One extra bit sits between the ack history and the packet-info payload; consuming
it realigns bHasPacketInfoPayload + jitter + bHasServerFrameTime, and the first
control-channel bunch parses (ChIndex 0, open, reliable = NMT_Hello).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/Prospect.Unreal/Net/UNetConnection.cs

@@ -532,6 +532,19 @@ public abstract class UNetConnection : UPlayer
                 return;
             }
 
+            // The Cycle client (UE4 R3.5.0) writes one extra bit between the packet's
+            // ack history and the packet-info payload that stock UE 4.27 (EngineNetVer
+            // 16) does not. Bit-decoding real client packets showed the header is 65
+            // bits, not 64: consuming this bit realigns everything downstream — the
+            // bHasPacketInfoPayload flag, the 10-bit jitter clock and bHasServerFrameTime
+            // then land exactly, and the first control-channel bunch parses cleanly
+            // (ChIndex 0, NMT_Hello). Observed always 0 in captures.
+            var bCycleExtraHeaderBit = reader.ReadBit();
+            if (bCycleExtraHeaderBit)
+            {
+                Logger.Warning("[HS-HDR] Cycle extra header bit was set (expected 0)");
+            }
+
             var bHasPacketInfoPayload = true;
             
             if (reader.EngineNetVer() > EEngineNetworkVersionHistory.HISTORY_JITTER_IN_HEADER)