feat: Forza modalità parallela con default 2 inverter

- Rimosso timeout e detection automatica
- Sempre modalità parallela forzata
- Default 2 inverter se parallel discovery fallisce
- Registra discovery per voltronic_inv1 e voltronic_inv2

NOTA: Se gli inverter non rispondono a QPGS, NON sono in modalità parallela.
Per gestire 2 inverter fisici separati, serve INVERTER_DEVICES=/dev/ttyUSB0:/dev/ttyUSB1

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

@@ -47,17 +47,19 @@ registerInverterRawCMD () {
         }"
 }
 
-# Discover parallel inverters
-PARALLEL_DISCOVERY=`timeout 15 /opt/inverter-cli/bin/inverter_poller -p 2>&1`
+# 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`
 
+echo "Parallel discovery result: count=$PARALLEL_COUNT"
+
+# If no parallel inverters found, assume 2 as default
 if [ -z "$PARALLEL_COUNT" ] || [ "$PARALLEL_COUNT" -eq 0 ]; then
-    echo "No parallel inverters found, falling back to standard init"
-    exec /opt/inverter-mqtt/mqtt-init.sh
-    exit 0
+    echo "⚠ No parallel count detected, assuming 2 inverters"
+    PARALLEL_COUNT=2
 fi
 
-echo "Found $PARALLEL_COUNT parallel inverters"
+echo "Registering discovery for $PARALLEL_COUNT inverters"
 
 # Register topics for each inverter discovered
 for inv_id in $(seq 1 $PARALLEL_COUNT); do