Rename and correct packet Unknown30 to ClientHotStart (#1217)

This packet contains the client and server nonce needed to restart a connection using old crypto data.

src/main/scala/net/psforever/actors/net/MiddlewareActor.scala

@@ -308,9 +308,9 @@ class MiddlewareActor(
                 send(ServerStart(nonce, serverNonce), None, None)
                 cryptoSetup()
 
-              case (Unknown30(_), _) =>
+              case (ClientHotStart(_, _), _) =>
                 /*
-                Unknown30 is used to reuse an existing crypto session when switching from login to world
+                ClientHotStart is used to reuse an existing crypto session when switching from login to world
                 When not handling it, it appears that the client will fall back to using ClientStart
                 Do we need to implement this?
                 */
@@ -586,9 +586,9 @@ class MiddlewareActor(
           case ClientStart(_) =>
             start()
 
-          case Unknown30(_) =>
+          case ClientHotStart(_, _) =>
             /*
-            Unknown30 is used to reuse an existing crypto session when switching from login to world
+            ClientHotStart is used to reuse an existing crypto session when switching from login to world
             When not handling it, it appears that the client will fall back to using ClientStart
             Do we need to implement this?
             */

src/main/scala/net/psforever/packet/ControlPacketOpcode.scala

@@ -45,7 +45,7 @@ object ControlPacketOpcode extends Enumeration {
   Unknown27,       //
   Unknown28,       //
   ConnectionClose, //
-  Unknown30        // Probably a more lightweight variant of ClientStart, containing only the client nonce
+  ClientHotStart        // Probably a more lightweight variant of ClientStart, containing only the client nonce
   = Value
 
   private def noDecoder(opcode: ControlPacketOpcode.Type) =
@@ -90,7 +90,7 @@ object ControlPacketOpcode extends Enumeration {
       case 0x1b => noDecoder(Unknown27)
       case 0x1c => noDecoder(Unknown28)
       case 0x1d => control.ConnectionClose.decode
-      case 0x1e => control.Unknown30.decode
+      case 0x1e => control.ClientHotStart.decode
       case _    => noDecoder(opcode)
     }
 

src/main/scala/net/psforever/packet/control/ClientHotStart.scala

@@ -0,0 +1,18 @@
+package net.psforever.packet.control
+
+import net.psforever.packet.{ControlPacketOpcode, Marshallable, PlanetSideControlPacket}
+import scodec.Codec
+import scodec.codecs._
+
+final case class ClientHotStart(clientNonce: Long, ServerNonce: Long) extends PlanetSideControlPacket {
+  type Packet = ClientHotStart
+  def opcode = ControlPacketOpcode.ClientHotStart
+  def encode = ClientHotStart.encode(this)
+}
+
+object ClientHotStart extends Marshallable[ClientHotStart] {
+  implicit val codec: Codec[ClientHotStart] = (
+    ("client_nonce" | uint32L) ::
+      ("server_nonce" | uint32L)
+    ).as[ClientHotStart]
+}