feat: Auto-discovery parallelo con timeout e stile originale

- Aggiunto timeout 15s al parallel discovery per evitare blocchi
- mqtt-init-parallel.sh in stile originale semplice
- Per ogni inverter scoperto: registra topic discovery (voltronic_inv1_*, inv2_*, ...)
- Discovery topics ogni 10 minuti invece di 5
- Fallback automatico a single-mode se timeout o count=0
- Mantiene la semplicità dello script originale

Il parallel discovery testa QPGS0-9 per trovare inverter configurati in parallelo.
Se timeout o nessun inverter trovato, usa modalità standard.

sources/inverter-mqtt/entrypoint.sh

@@ -241,20 +241,33 @@ echo ""
 # Wait a bit for the device to be ready
 sleep 2
 
-# Check for parallel inverters
-PARALLEL_CHECK=$(/opt/inverter-cli/bin/inverter_poller -p 2>&1)
-PARALLEL_COUNT=$(echo "$PARALLEL_CHECK" | grep "PARALLEL_COUNT=" | cut -d= -f2)
+# Check for parallel inverters (with timeout to avoid hanging)
+echo "Checking for parallel inverters..."
+PARALLEL_CHECK=$(timeout 15 /opt/inverter-cli/bin/inverter_poller -p 2>&1)
+PARALLEL_EXIT=$?
 
-if [ ! -z "$PARALLEL_COUNT" ] && [ "$PARALLEL_COUNT" -gt 0 ]; then
-    echo "✓ Detected $PARALLEL_COUNT parallel inverter(s)"
-    echo "  Using parallel mode scripts..."
-    USE_PARALLEL=true
+if [ $PARALLEL_EXIT -eq 124 ]; then
+    echo "⚠ Parallel discovery timed out (15s), using single inverter mode"
+    USE_PARALLEL=false
+else
+    PARALLEL_COUNT=$(echo "$PARALLEL_CHECK" | grep "PARALLEL_COUNT=" | cut -d= -f2)
+    
+    if [ ! -z "$PARALLEL_COUNT" ] && [ "$PARALLEL_COUNT" -gt 0 ]; then
+        echo "✓ Detected $PARALLEL_COUNT parallel inverter(s)"
+        echo "  Using parallel mode scripts..."
+        USE_PARALLEL=true
+    else
+        echo "ℹ Single inverter mode (count=$PARALLEL_COUNT)"
+        echo "  Using standard scripts..."
+        USE_PARALLEL=false
+    fi
+fi
+
+# Set script paths based on mode
+if [ "$USE_PARALLEL" = true ]; then
     MQTT_PUSH_SCRIPT="/opt/inverter-mqtt/mqtt-push-parallel.sh"
     MQTT_INIT_SCRIPT="/opt/inverter-mqtt/mqtt-init-parallel.sh"
 else
-    echo "ℹ Single inverter mode"
-    echo "  Using standard scripts..."
-    USE_PARALLEL=false
     MQTT_PUSH_SCRIPT="/opt/inverter-mqtt/mqtt-push.sh"
     MQTT_INIT_SCRIPT="/opt/inverter-mqtt/mqtt-init.sh"
 fi