add guard Lightning usage with isInitialized check (#3128)

cw_bitcoin/lib/bitcoin_wallet.dart

@@ -164,6 +164,8 @@ abstract class BitcoinWalletBase extends ElectrumWallet with Store {
     }
   }
 
+  bool get isLightningInitialized => lightningWallet?.isInitialized == true;
+
   @override
   bool get hasRescan => true;
 
@@ -339,7 +341,7 @@ abstract class BitcoinWalletBase extends ElectrumWallet with Store {
   @override
   Future<ElectrumBalance> fetchBalances() async {
     final balance = await super.fetchBalances();
-    if (lightningWallet == null) {
+    if (!isLightningInitialized || lightningWallet == null) {
       return balance;
     }
 
@@ -358,7 +360,7 @@ abstract class BitcoinWalletBase extends ElectrumWallet with Store {
   @override
   @action
   Future<void> subscribeForUpdates() async {
-    if (lightningWallet != null) {
+    if (isLightningInitialized && lightningWallet != null) {
       lightningWallet!.setEventListener(
         onTransactionEvent: (tx) async {
           if (transactionHistory.transactions[tx.id]?.isPending != tx.isPending) {

cw_bitcoin/lib/lightning/lightning_wallet.dart

@@ -41,6 +41,8 @@ class LightningWallet {
 
   StreamSubscription<LogEntry>? _logSubscription;
 
+  bool get isInitialized => _eventStream != null;
+
   void _subscribeToLogStream(File logFile) {
     _logSubscription = _logStream?.listen((logEntry) {
       logFile.writeAsStringSync("[${logEntry.level}] ${logEntry.line}\n", mode: FileMode.append);