Rename VIN_THRESHOLD entity to Input voltage threshold

It is a voltage level, not a power quantity.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

hassio-addon-lifepo4wered/config.json

@@ -1,6 +1,6 @@
 {
   "name": "LiFePO4wered Addon",
-  "version": "0.1.1",
+  "version": "0.1.2",
   "init": false,
   "slug": "lifepo4wered",
   "description": "Add-on with service and MQTT monitor for LiFePO4wered/Pi+ UPS",

hassio-addon-lifepo4wered/lifepo4wered_monitor.py

@@ -84,7 +84,7 @@ DIAG_VOLTAGE = [
     ("VBAT_SHDN", "Battery shutdown voltage"),
     ("VBAT_BOOT", "Battery boot voltage"),
     ("VOUT_MAX", "Output maximum voltage"),
-    ("VIN_THRESHOLD", "Input power threshold"),
+    ("VIN_THRESHOLD", "Input voltage threshold"),
 ]
 
 # raw-value diagnostic registers (units vary or are unitless flags/timers)