Add default values for hive fields for Node, UnspentCoinsInfo, Wallet… (#598)

* Add default values for hive fields for Node, UnspentCoinsInfo, WalletInfo, Order, Contact, TransactionDescription, Trade

cw_core/lib/node.dart

@@ -36,7 +36,7 @@ class Node extends HiveObject with Keyable {
   static const typeId = 1;
   static const boxName = 'Nodes';
 
-  @HiveField(0)
+  @HiveField(0, defaultValue: '')
   late String uriRaw;
 
   @HiveField(1)
@@ -45,7 +45,7 @@ class Node extends HiveObject with Keyable {
   @HiveField(2)
   String? password;
 
-  @HiveField(3)
+  @HiveField(3, defaultValue: 0)
   late int typeRaw;
 
   @HiveField(4)

cw_core/lib/unspent_coins_info.dart

@@ -15,16 +15,16 @@ class UnspentCoinsInfo extends HiveObject {
   static const boxName = 'Unspent';
   static const boxKey = 'unspentBoxKey';
 
-  @HiveField(0)
+  @HiveField(0, defaultValue: '')
   String walletId;
 
-  @HiveField(1)
+  @HiveField(1, defaultValue: '')
   String hash;
 
-  @HiveField(2)
+  @HiveField(2, defaultValue: false)
   bool isFrozen;
 
-  @HiveField(3)
+  @HiveField(3, defaultValue: false)
   bool isSending;
 
   @HiveField(4)

cw_core/lib/wallet_info.dart

@@ -33,31 +33,31 @@ class WalletInfo extends HiveObject {
   static const typeId = 4;
   static const boxName = 'WalletInfo';
 
-  @HiveField(0)
+  @HiveField(0, defaultValue: '')
   String id;
 
-  @HiveField(1)
+  @HiveField(1, defaultValue: '')
   String name;
 
   @HiveField(2)
   WalletType type;
 
-  @HiveField(3)
+  @HiveField(3, defaultValue: false)
   bool isRecovery;
 
-  @HiveField(4)
+  @HiveField(4, defaultValue: 0)
   int restoreHeight;
 
-  @HiveField(5)
+  @HiveField(5, defaultValue: 0)
   int timestamp;
 
-  @HiveField(6)
+  @HiveField(6, defaultValue: '')
   String dirPath;
 
-  @HiveField(7)
+  @HiveField(7, defaultValue: '')
   String path;
 
-  @HiveField(8)
+  @HiveField(8, defaultValue: '')
   String address;
 
   @HiveField(10)