Add v210 upload worker probe

AppConfig.cpp

@@ -577,6 +577,10 @@ bool applyConfigFile(
     {
         config.paceUploads = boolValue;
     }
+    if (jsonBool(objectField(*root, "v210UploadWorker"), boolValue))
+    {
+        config.v210UploadWorker = boolValue;
+    }
 
     if (const std::string* present =
             jsonString(objectField(*root, "present")))
@@ -809,6 +813,7 @@ void printUsage(const char* executableName)
         << "  --perf                Log per-frame CPU timing breakdown\n"
         << "  --verbose             Enable detailed startup and SDK logs\n"
         << "  --pace-uploads        Pace v210 uploads by feed frame rate\n"
+        << "  --v210-upload-worker  Copy direct v210 payloads on a worker thread\n"
         << "  --config <path>       Load JSON feed configuration\n"
         << "  --grid <cols>x<rows>  Set multiview grid (default 2x2, max 16 feeds)\n"
         << "  --fps-cap <fps>       Limit render loop FPS (default 60)\n"
@@ -955,6 +960,12 @@ ConfigParseResult parseAppConfig(
             continue;
         }
 
+        if (arg == "--v210-upload-worker")
+        {
+            result.config.v210UploadWorker = true;
+            continue;
+        }
+
         if (arg == "--v210-staging-memory")
         {
             if (i + 1 >= argc)