feat(app): Flutter-клиент — логин, дашборд, потоки, категории, транзакции, правила

Riverpod + go_router с auth-guard, NavigationRail на широком экране и bottom bar
на узком. Токены в flutter_secure_storage, на web access живёт в памяти.
Интерцептор подставляет токен и делает ровно один refresh на 401.

Деньги приходят строками и форматируются через Decimal: парсить их в double
значило бы терять копейки ровно там, где бэкенд их бережёт.

app/test/app_shell_test.dart

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+import 'package:fintracker_app/features/shell/app_shell.dart';
+import 'package:flutter/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+
+void main() {
+  Widget wrap(double width) {
+    return MediaQuery(
+      data: MediaQueryData(size: Size(width, 800)),
+      child: MaterialApp(
+        home: AppShell(location: '/', child: Container()),
+      ),
+    );
+  }
+
+  testWidgets('shows a NavigationRail on a wide surface', (tester) async {
+    await tester.pumpWidget(wrap(1280));
+    expect(find.byType(NavigationRail), findsOneWidget);
+    expect(find.byType(NavigationBar), findsNothing);
+  });
+
+  testWidgets('shows a bottom NavigationBar on a narrow surface', (tester) async {
+    await tester.pumpWidget(wrap(400));
+    expect(find.byType(NavigationBar), findsOneWidget);
+    expect(find.byType(NavigationRail), findsNothing);
+  });
+}

app/test/date_query_interceptor_test.dart

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+import 'package:dio/dio.dart';
+import 'package:fintracker_app/core/api/api_client.dart';
+import 'package:flutter_test/flutter_test.dart';
+
+/// Captures whatever `onRequest` passes on, so the rewritten query can be inspected.
+class _Capture extends RequestInterceptorHandler {
+  RequestOptions? seen;
+
+  @override
+  void next(RequestOptions options) => seen = options;
+}
+
+void main() {
+  RequestOptions run(Map<String, dynamic> query) {
+    final handler = _Capture();
+    DateQueryInterceptor().onRequest(
+      RequestOptions(path: '/networth/series', queryParameters: query),
+      handler,
+    );
+    return handler.seen!;
+  }
+
+  test('a DateTime becomes a plain YYYY-MM-DD date', () {
+    // the value the generated client hands over: DateTime.now(), time and all
+    final out = run({'from': DateTime(2025, 9, 18, 10, 31, 29, 84)});
+    expect(out.queryParameters['from'], '2025-09-18');
+  });
+
+  test('single-digit months and days keep two digits', () {
+    final out = run({'from': DateTime(2026, 1, 5)});
+    expect(out.queryParameters['from'], '2026-01-05');
+  });
+
+  test('non-date parameters are passed through untouched', () {
+    final out = run({'page': 2, 'q': 'кофе', 'include_deleted': false});
+    expect(out.queryParameters, {'page': 2, 'q': 'кофе', 'include_deleted': false});
+  });
+}

app/test/home_page_test.dart

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+import 'package:fintracker_api/fintracker_api.dart';
+import 'package:fintracker_app/core/widgets/money_text.dart';
+import 'package:fintracker_app/features/home/home_page.dart';
+import 'package:fintracker_app/features/home/providers.dart';
+import 'package:flutter/material.dart';
+import 'package:flutter_riverpod/flutter_riverpod.dart';
+import 'package:flutter_test/flutter_test.dart';
+
+void main() {
+  testWidgets('Обзор renders stat tiles from a net worth breakdown', (tester) async {
+    final breakdown = NetWorthBreakdown(
+      accounts: const [],
+      byCurrency: const {'RUB': '123456.78'},
+      d: DateTime(2026, 9, 17),
+      debtRub: '1000',
+      investmentRub: '2000',
+      liquidRub: '3000',
+      missingFxCount: 0,
+      savingsRub: '4000',
+      totalRub: '123456.78',
+    );
+
+    await tester.pumpWidget(
+      ProviderScope(
+        overrides: [
+          netWorthBreakdownProvider.overrideWith((ref) => breakdown),
+          netWorthSeriesProvider.overrideWith((ref) => const <NetWorthDay>[]),
+          cashflowThisMonthProvider.overrideWith((ref) => null),
+          cashflowLast12Provider.overrideWith((ref) => const <CashFlowMonth>[]),
+          runwayProvider.overrideWith((ref) => RunwayOut(
+                asOf: DateTime(2026, 9, 17),
+                avgBaseline3mRub: '0',
+                liquidReserveRub: '0',
+                runwayMonths: null,
+              )),
+          metricsStatusProvider.overrideWith((ref) => null),
+          dataQualityProvider.overrideWith((ref) => const <DataQualityRow>[]),
+        ],
+        child: const MaterialApp(home: HomePage()),
+      ),
+    );
+    await tester.pumpAndSettle();
+
+    expect(find.text('Капитал сегодня'), findsOneWidget);
+    expect(find.text(MoneyText.format('123456.78', 'RUB')), findsOneWidget);
+    expect(find.text('Ликвидные'), findsOneWidget);
+    expect(find.text(MoneyText.format('3000', 'RUB')), findsOneWidget);
+    expect(find.text('Долги'), findsOneWidget);
+    expect(find.text(MoneyText.format('1000', 'RUB')), findsOneWidget);
+  });
+}

app/test/money_text_test.dart

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+import 'package:fintracker_app/core/widgets/money_text.dart';
+import 'package:flutter_test/flutter_test.dart';
+
+void main() {
+  test('formats a decimal-string RUB amount with ru_RU grouping', () {
+    // intl's ru_RU locale data uses U+00A0 (NBSP) as both the group and
+    // currency separator, so the expected string is not plain ASCII spaces.
+    expect(MoneyText.format('1234.5', 'RUB'), '1 234,50 ₽');
+  });
+}

app/test/rules_page_test.dart

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+import 'package:fintracker_api/fintracker_api.dart';
+import 'package:fintracker_app/features/rules/providers.dart';
+import 'package:fintracker_app/features/rules/rules_page.dart';
+import 'package:flutter/material.dart';
+import 'package:flutter_riverpod/flutter_riverpod.dart';
+import 'package:flutter_test/flutter_test.dart';
+
+void main() {
+  testWidgets('the add-rule dialog requires a non-empty pattern', (tester) async {
+    await tester.pumpWidget(
+      ProviderScope(
+        overrides: [
+          rulesListProvider.overrideWith((ref) => const <RuleOut>[]),
+          rulesStaleProvider.overrideWith((ref) => const <RuleOut>[]),
+        ],
+        child: const MaterialApp(home: RulesPage()),
+      ),
+    );
+    await tester.pumpAndSettle();
+
+    await tester.tap(find.byIcon(Icons.add));
+    await tester.pumpAndSettle();
+
+    expect(find.text('Новое правило'), findsOneWidget);
+
+    await tester.tap(find.text('Сохранить'));
+    await tester.pumpAndSettle();
+
+    expect(find.text('Обязательное поле'), findsOneWidget);
+  });
+}

app/test/transaction_row_test.dart

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+import 'package:fintracker_api/fintracker_api.dart';
+import 'package:fintracker_app/core/widgets/money_text.dart';
+import 'package:fintracker_app/features/transactions/transaction_row.dart';
+import 'package:flutter/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+
+TransactionOut _usdExpense() => TransactionOut(
+      categoryId: 1,
+      comment: null,
+      date: DateTime(2026, 9, 10),
+      deleted: false,
+      flowType: FlowType.expense,
+      hold: false,
+      id: 1,
+      income: '0',
+      incomeAccountId: null,
+      incomeCurrency: null,
+      incomeRub: null,
+      isOneOff: false,
+      mcc: null,
+      outcome: '100',
+      outcomeAccountId: 7,
+      outcomeCurrency: 'USD',
+      outcomeRub: '9500.00',
+      payee: 'Amazon.com',
+      payeeCanonical: 'Amazon',
+      sourceId: 'src-1',
+      tags: const [],
+      tripId: null,
+      ts: DateTime(2026, 9, 10),
+    );
+
+void main() {
+  testWidgets('shows a USD amount with its RUB equivalent as secondary text', (tester) async {
+    await tester.pumpWidget(
+      MaterialApp(
+        home: Scaffold(
+          body: TransactionRow(
+            transaction: _usdExpense(),
+            categoryName: 'Покупки',
+            onTap: () {},
+          ),
+        ),
+      ),
+    );
+
+    expect(find.text('Amazon'), findsOneWidget);
+    expect(find.text(MoneyText.format('100', 'USD')), findsOneWidget);
+    expect(find.text(MoneyText.format('9500.00', 'RUB')), findsOneWidget);
+  });
+}

app/test/widget_test.dart

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+import 'package:fintracker_app/core/auth/auth_controller.dart';
+import 'package:flutter_test/flutter_test.dart';
+
+void main() {
+  test('AuthState.signedIn reflects status', () {
+    expect(const AuthState(AuthStatus.signedIn, accessToken: 't').signedIn, isTrue);
+    expect(const AuthState(AuthStatus.signedOut).signedIn, isFalse);
+  });
+}