feat(capture): record whole packets of an account, a character or everything on every server

Staff arm a packet capture on the dashboard; master passes MESSAGE_CAPTURE_CONTROL ARM to
every world, auth and chat and arms its own. Each server's PacketCapture tap (dServer receive,
and a send hook in RakPeer::Send so replica constructions are seen too) records into one
preallocated chunk per server and ships sealed chunks through master on the main loop when
capture_flush_bytes or capture_flush_interval_ms is reached; past capture_buffer_max_mb the
oldest chunks are dropped and the dashboard records a gap. Nothing is armed: one flag check.

- targets: an account (from its login; packets before the login are kept per connection
  and added once auth or the world knows whose they are), a character (from when it is
  picked), or everything; up to 8 at once (a bit each in the record mask)
- worlds and auth record their clients' packets and the master link messages of a captured
  player (session keys by name, zone transfers by request, player added/removed, migration);
  chat finds the player in each packet; master records server traffic for everything
- secrets are never recorded: structs that carry them (login request, login response user
  key, world validation session key, session key messages between servers) are read,
  blanked and written again before recording; auth keeps only the handshake and login
- PacketDecoder: a registry by service and message id names every packet and decodes the
  registered structs; CaptureBundle is the file format (DLUBNDL1, metadata, records);
  CaptureTools orders records on one timeline, pulls movement out, makes bundles portable
  or anonymous and diffs replays
- the dashboard keeps packet captures in message_capture_sessions (capture_kind 1) and
  their packets in a file under capture_dir, one write per batch; arming is audited
- MESSAGE_CAPTURE_CONTROL/DATA only gain appended enum values and trailing fields

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

thirdparty/raknet/Source/RakPeer.cpp

@@ -975,6 +975,8 @@ bool RakPeer::GetConnectionList( SystemAddress *remoteSystems, unsigned short *n
 // Returns:
 // False if we are not connected to the specified recipient.  True otherwise
 // --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
+RakPeerSendHook g_RakPeerSendHook = 0;
+
 bool RakPeer::Send( const char *data, const int length, PacketPriority priority, PacketReliability reliability, char orderingChannel, SystemAddress systemAddress, bool broadcast )
 {
 #ifdef _DEBUG
@@ -990,6 +992,9 @@ bool RakPeer::Send( const char *data, const int length, PacketPriority priority,
 	if ( broadcast == false && systemAddress == UNASSIGNED_SYSTEM_ADDRESS )
 		return false;
 
+	if (g_RakPeerSendHook)
+		g_RakPeerSendHook(this, (const unsigned char*)data, BYTES_TO_BITS(length), systemAddress, broadcast);
+
 	if (broadcast==false && router && IsConnected(systemAddress)==false)
 	{
 		return router->Send(data, BYTES_TO_BITS(length), priority, reliability, orderingChannel, systemAddress);
@@ -1017,6 +1022,9 @@ bool RakPeer::Send( const RakNet::BitStream * bitStream, PacketPriority priority
 	if ( broadcast == false && systemAddress == UNASSIGNED_SYSTEM_ADDRESS )
 		return false;
 
+	if (g_RakPeerSendHook)
+		g_RakPeerSendHook(this, bitStream->GetData(), bitStream->GetNumberOfBitsUsed(), systemAddress, broadcast);
+
 	if (broadcast==false && router && IsConnected(systemAddress)==false)
 	{
 		return router->Send((const char*)bitStream->GetData(), bitStream->GetNumberOfBitsUsed(), priority, reliability, orderingChannel, systemAddress);

thirdparty/raknet/Source/RakPeer.h

@@ -42,6 +42,11 @@ int RAK_DLL_EXPORT SystemAddressAndIndexComp( const SystemAddress &key, const Sy
 /// The primary interface for RakNet, RakPeer contains all major functions for the library.
 /// See the individual functions for what the class can do.
 /// \brief The main interface for network communications
+/// DLU addition: called on the caller's thread for every packet the application sends with Send (not RakNet's own
+/// connection messages), before it is queued. The server's packet capture sets it only while a capture is armed.
+typedef void (*RakPeerSendHook)(RakPeerInterface* peer, const unsigned char* data, BitSize_t bits, SystemAddress systemAddress, bool broadcast);
+extern RakPeerSendHook g_RakPeerSendHook;
+
 class RAK_DLL_EXPORT RakPeer : public RakPeerInterface
 {
 public: