app working with sandbox

lib/models/bank.dart

@@ -0,0 +1,112 @@
+/// Domain models for the personal ingtrak bank-data API.
+library;
+
+/// Result of `POST /api/connect`.
+class ConnectStart {
+  const ConnectStart({required this.authUrl, required this.state});
+
+  final String authUrl;
+  final String state;
+
+  factory ConnectStart.fromJson(Map<String, dynamic> json) {
+    return ConnectStart(
+      authUrl: json['authUrl'] as String? ?? '',
+      state: json['state'] as String? ?? '',
+    );
+  }
+}
+
+/// Link status from `/api/connect/status` or `/api/connect/complete`.
+class ConnectStatus {
+  const ConnectStatus({
+    required this.status,
+    required this.linked,
+    this.accountId,
+    this.sessionId,
+    this.state,
+    this.validUntil,
+  });
+
+  final String status;
+  final bool linked;
+  final String? accountId;
+  final String? sessionId;
+  final String? state;
+  final String? validUntil;
+
+  factory ConnectStatus.fromJson(Map<String, dynamic> json) {
+    return ConnectStatus(
+      status: json['status'] as String? ?? 'unknown',
+      linked: json['linked'] as bool? ?? false,
+      accountId: json['accountId'] as String?,
+      sessionId: json['sessionId'] as String?,
+      state: json['state'] as String?,
+      validUntil: json['validUntil'] as String?,
+    );
+  }
+
+  static const disconnected = ConnectStatus(
+    status: 'disconnected',
+    linked: false,
+  );
+}
+
+/// `GET /api/balance` payload.
+class BankBalance {
+  const BankBalance({
+    required this.amount,
+    required this.currency,
+    this.balanceType,
+  });
+
+  final double amount;
+  final String currency;
+  final String? balanceType;
+
+  factory BankBalance.fromJson(Map<String, dynamic> json) {
+    final rawAmount = json['amount'];
+    final amount = switch (rawAmount) {
+      num n => n.toDouble(),
+      String s => double.tryParse(s) ?? 0,
+      _ => 0.0,
+    };
+    return BankBalance(
+      amount: amount,
+      currency: json['currency'] as String? ?? 'EUR',
+      balanceType: json['balanceType'] as String?,
+    );
+  }
+}
+
+/// One row from `GET /api/transactions`.
+class BankTransaction {
+  const BankTransaction({
+    required this.date,
+    required this.description,
+    required this.amount,
+    required this.currency,
+    required this.pending,
+  });
+
+  final String date;
+  final String description;
+  final double amount;
+  final String currency;
+  final bool pending;
+
+  factory BankTransaction.fromJson(Map<String, dynamic> json) {
+    final rawAmount = json['amount'];
+    final amount = switch (rawAmount) {
+      num n => n.toDouble(),
+      String s => double.tryParse(s) ?? 0,
+      _ => 0.0,
+    };
+    return BankTransaction(
+      date: json['date'] as String? ?? '',
+      description: json['description'] as String? ?? 'Unknown',
+      amount: amount,
+      currency: json['currency'] as String? ?? 'EUR',
+      pending: json['pending'] as bool? ?? false,
+    );
+  }
+}