Seed socket payloads with opt (communicate factory) + host_probe4

docs/BATTERY_POC.md

@@ -69,6 +69,11 @@ python3 -m franklinwh_agate_client.battery \
   --sn A03X2516013210060005 --host 10.100.1.1 --ports 9000,18000 --probe
 ```
 
+> Prefer the standalone scripts in `scripts/` — they need no install and
+> track the latest corrections: `host_probe4.py` is current (socket-space
+> ids + `opt`-seeded payloads). Copy the file content and run
+> `python3 host_probe4.py --sn A03X2516013210060005 --ports 9000`.
+
 Expected: `secret key for ...: 1c (radix 32)`, then per-variant `tx`
 (encrypted envelope, starts with the ASCII header
 `{"cmdType":25,"equipNo":"A03X2516013210060005",`) and `rx` bytes.