canbus: confirm command path live + frame docs as device integration

Command path proven end to end on the bus (node F8 interior lights, on/off/on),
each answering a distinct fresh challenge; bare opcodes without the exchange are
ignored. ids_can_auth.h verified bit-exact against ids_can_auth.py and the
captured/live pairs.

- idscan_cmd.py: stdlib socketcan tool running the full page-42/43 exchange
- esphome/onecontrol-canbus.yaml: correct IDS-CAN read dispatch (was stale RV-C
  DGN code) + command path wired to the auth header
- README/memory: document the read map + command authentication; rename
  sniff/ -> captures/; neutral device-integration framing throughout

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

canbus/esphome/ids_can_auth.h

@@ -1,5 +1,5 @@
 #pragma once
-// IDS-CAN command-auth response cipher for the OneControl write path.
+// IDS-CAN command authentication response for the OneControl integration.
 //
 // 32-round TEA/XTEA-family Feistel, delta 0x9E3779B9, keyed by a per-session
 // 32-bit "Cypher" with the round constants baked in.
@@ -13,7 +13,7 @@
 
 namespace ids_can_auth {
 
-// Per-session keys ("Cypher"). REMOTE_CONTROL gates on/off/move.
+// Per-session keys ("Cypher"). REMOTE_CONTROL is the session for on/off/move.
 enum SessionKey : uint32_t {
   MANUFACTURING  = 0xB16BA115u,
   DIAGNOSTIC     = 0xBABECAFEu,