feat(tcp): TCPStreamer DataSources, in-process TCPStreamService, stream multiplexing and TCPStreamJoin

Add TCPStreamer/TCPStreamerClient (TCP transport behind the UDPSServerI/UDPSClientI
seam), an optional single in-process TCPStreamService serving many streams over
worker threads, multiplexed SUBSCRIBE (comma list, stream index in fragmentIdx),
and TCPStreamJoin, which merges several streams into one sample-and-hold stream
paced by a master. StreamHub takes a comma list of streams over one connection.
Includes GTests, E2E scenarios s58-s73 and docs.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Source/Components/Interfaces/UDPStream/UDPSServer.h

@@ -23,6 +23,7 @@
 #include "StreamString.h"
 #include "StructuredDataI.h"
 #include "UDPSProtocol.h"
+#include "UDPSTransportI.h"
 
 namespace MARTe {
 
@@ -43,7 +44,7 @@ namespace MARTe {
  *   server.Stop();                    // in StopCurrentStateExecution()
  * @endcode
  */
-class UDPSServer {
+class UDPSServer : public UDPSServerI {
 public:
 
     /** Maximum number of simultaneous unicast clients. */