Remove bb- prefix from device ID default

bb- prefix is a tool fingerprint — visible in Infisical key names,
alerter payloads, and config files on the device. Default is now
a plain 10-char hex string with no identifying prefix.

operator_setup.sh

@@ -221,10 +221,10 @@ else
     error "Invalid SSH option"
 fi
 
-# Device ID
+# Device ID — no tool fingerprint in default
 step "Device ID"
-DEFAULT_DEVICE_ID="bb-$(cat /proc/sys/kernel/random/uuid | cut -c1-8)"
-prompt_default device_id "Device label (e.g. bb-a3f2c1)" "$DEFAULT_DEVICE_ID"
+DEFAULT_DEVICE_ID=$(cat /proc/sys/kernel/random/uuid | tr -d '-' | cut -c1-10)
+prompt_default device_id "Device label (e.g. a3f2c19d08)" "$DEFAULT_DEVICE_ID"
 DEVICE_ID="$device_id"
 
 # Hostname — pick from MAC device profiles (matches MAC identity)