Ad hoc: Options to simulate a slow network

--adhoc-delay, --adhoc-jitter and --adhoc-loss (AdhocSimDelayMs, AdhocSimJitterMs and
AdhocSimLossPercent in the ini) delay and drop ad hoc traffic, in emulated time, to find games that
can't cope with a real network's latency.

They're a transport, NetSimTransport, around whichever one is in use, so they work the same for the
relay and P2P. PDP datagrams are held on arrival; PTP sends are held before they go, and a "lost" one
goes a retransmit interval later instead. PtpSendNow is new in the transports, for those delayed sends.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

Core/Config.cpp

@@ -1419,6 +1419,9 @@ static constexpr ConfigSetting networkSettings[] = {
 	ConfigSetting("PortOffset", SETTING(g_Config, iPortOffset), 10000, CfgFlag::PER_GAME)
 		.Label(I18NCat::NETWORKING, "Port offset").Range(0, 60000, 100),
 	ConfigSetting("PrimaryDNSServer", SETTING(g_Config, sInfrastructureDNSServer), "67.222.156.250", CfgFlag::PER_GAME),
+	ConfigSetting("AdhocSimDelayMs", SETTING(g_Config, iAdhocSimDelayMs), 0, CfgFlag::DEFAULT),
+	ConfigSetting("AdhocSimJitterMs", SETTING(g_Config, iAdhocSimJitterMs), 0, CfgFlag::DEFAULT),
+	ConfigSetting("AdhocSimLossPercent", SETTING(g_Config, iAdhocSimLossPercent), 0, CfgFlag::DEFAULT),
 	ConfigSetting("MinTimeout", SETTING(g_Config, iMinTimeout), 0, CfgFlag::PER_GAME)
 		.Label(I18NCat::NETWORKING, "Minimum Timeout", "Minimum Timeout (override in ms, 0 = default)").Range(0, 15000, 50).Units("ms"),
 	ConfigSetting("ForcedFirstConnect", SETTING(g_Config, bForcedFirstConnect), false, CfgFlag::PER_GAME)