Add bench UART ports and cold-start reset to goTool autotest.

Bench configs define command and console serial paths; scenarios can
reset nodes via esptool before tests. Smoke resets all nodes then waits
for ESP-NOW join.

Co-authored-by: Cursor <cursoragent@cursor.com>

goTool/testdata/configs/example-lab.json

@@ -1,13 +1,19 @@
 {
   "id": "example-lab",
-  "description": "Example bench — replace MACs and network with your hardware",
+  "description": "Example bench — replace MACs, network, and serial paths",
   "network": 1,
   "master_mac": "50:78:7d:18:00:10",
+  "uart": {
+    "baud": 921600,
+    "master": "/dev/ttyUSB0",
+    "master_console": "/dev/ttyACM0"
+  },
   "slaves": [
     {
       "id": "pod-1",
       "mac": "50:78:7d:18:01:10",
-      "client_id": 16
+      "client_id": 16,
+      "console": "/dev/ttyACM1"
     }
   ]
 }