Address code review feedback: remove unnecessary cast, add documentation and warnings

Co-authored-by: dorkmo <[email protected]>

Author: Copilot

TankAlarm-112025-Client-BluesOpta/TankAlarm-112025-Client-BluesOpta.ino

@@ -1880,7 +1880,7 @@ static float readNotecardVinVoltage() {
     return -1.0f;
   }
 
-  float voltage = (float)JGetNumber(rsp, "value");
+  float voltage = JGetNumber(rsp, "value");
   notecard.deleteResponse(rsp);
 
   if (voltage > 0.0f) {

TankAlarm-112025-Server-BluesOpta/TankAlarm-112025-Server-BluesOpta.ino

@@ -1203,6 +1203,9 @@ static const char DASHBOARD_HTML[] PROGMEM = R"HTML(
         return `${hours} h`;
       }
 
+      // Flatten client/tank hierarchy into rows for display.
+      // VIN voltage is a per-client value (from Blues Notecard), so it's only
+      // shown on the first tank row for each client to avoid redundancy.
       function flattenTanks(clients) {
         const rows = [];
         clients.forEach(client => {
@@ -3678,6 +3681,12 @@ static ClientMetadata *findOrCreateClientMetadata(const char *clientUid) {
     return meta;
   }
 
+  // Maximum client metadata capacity reached
+  Serial.print(F("Warning: Cannot create client metadata for "));
+  Serial.print(clientUid);
+  Serial.print(F(" - max capacity ("));
+  Serial.print(MAX_CLIENT_METADATA);
+  Serial.println(F(") reached"));
   return nullptr;
 }