feat: Flusso completo discovery parallelo per 2 inverter

FLUSSO IMPLEMENTATO:
1. All'avvio: registra discovery topics per 2 inverter (hardcoded)
2. Discovery topics ripetuti ogni 5 minuti (invece di 10)
3. Parallel discovery parametri con retry:
   - Tenta discovery fino a 3 volte
   - Se fallisce: attende 5s e riprova
   - Se tutti i tentativi falliscono: assume 2 inverter
4. Estrazione dati ogni 30s per entrambi gli inverter

NAMING:
- Inverter 1: voltronic_inv1_*
- Inverter 2: voltronic_inv2_*

Discovery topics include tutti i 33 parametri per entrambi gli inverter

sources/inverter-mqtt/mqtt-init-parallel.sh

@@ -1,6 +1,6 @@
 #!/bin/bash
 #
-# MQTT Discovery for Parallel Inverters (simple style)
+# MQTT Discovery for 2 Parallel Inverters (hardcoded)
 
 MQTT_SERVER=`cat /etc/inverter/mqtt.json | jq '.server' -r`
 MQTT_PORT=`cat /etc/inverter/mqtt.json | jq '.port' -r`
@@ -47,23 +47,13 @@ registerInverterRawCMD () {
         }"
 }
 
-# Discover parallel inverters (no timeout, always try)
-PARALLEL_DISCOVERY=`/opt/inverter-cli/bin/inverter_poller -p 2>&1`
-PARALLEL_COUNT=`echo "$PARALLEL_DISCOVERY" | grep "PARALLEL_COUNT=" | cut -d= -f2`
+# Always register for 2 inverters (hardcoded)
+INVERTER_COUNT=2
 
-echo "Parallel discovery result: count=$PARALLEL_COUNT"
+echo "Registering discovery topics for $INVERTER_COUNT inverters..."
 
-# If no parallel inverters found, assume 2 as default
-if [ -z "$PARALLEL_COUNT" ] || [ "$PARALLEL_COUNT" -eq 0 ]; then
-    echo "⚠ No parallel count detected, assuming 2 inverters"
-    PARALLEL_COUNT=2
-fi
-
-echo "Registering discovery for $PARALLEL_COUNT inverters"
-
-# Register topics for each inverter discovered
-for inv_id in $(seq 1 $PARALLEL_COUNT); do
-    echo "Registering discovery topics for inverter #$inv_id..."
+for inv_id in $(seq 1 $INVERTER_COUNT); do
+    echo "  Inverter #$inv_id..."
     
     registerTopic $inv_id "serial" "" "identifier"
     registerTopic $inv_id "Inverter_mode" "" "solar-power"
@@ -99,8 +89,7 @@ for inv_id in $(seq 1 $PARALLEL_COUNT); do
     registerTopic $inv_id "Charger_source_priority" "" "solar-power"
     registerTopic $inv_id "Battery_redischarge_voltage" "V" "battery-negative"
     
-    # Raw command topic
     registerInverterRawCMD $inv_id
 done
 
-echo "✓ All discovery topics registered for $PARALLEL_COUNT inverters"
+echo "✓ Discovery topics registered for $INVERTER_COUNT inverters"