feat(app): экраны импорта отчётов, целей, доходов, ребалансировки, налогов и бенчмарков

Импорт (/imports, /instruments/pending) и фаза 4 (/goals, /income,
/rebalance, /tax, аналитика-хаб с benchmarks_card) — по
docs/ai/import-contract.md и docs/ai/phase4-contract.md. file_picker для
загрузки отчёта.

app/lib/features/shell/analytics_page.dart

@@ -0,0 +1,69 @@
+import 'package:flutter/material.dart';
+import 'package:go_router/go_router.dart';
+
+/// Аналитика: a hub for the phase-4 screens.
+///
+/// Why a hub instead of four more destinations: the shell already carried eleven, which on
+/// a phone leaves ~36 px per label in the bottom bar. Доходы, Ребалансировка, Цели and
+/// Налоги are all "what do I do with the portfolio next" questions, so they live behind one
+/// entry that highlights for all four (see `alsoMatches` in `app_shell.dart`), while each
+/// keeps its own top-level route from the contract (`/income`, `/rebalance`, `/goals`,
+/// `/tax`) and is deep-linkable.
+class AnalyticsHubPage extends StatelessWidget {
+  const AnalyticsHubPage({super.key});
+
+  static const _entries = [
+    (
+      path: '/income',
+      icon: Icons.payments_outlined,
+      title: 'Доходы',
+      subtitle: 'Календарь дивидендов и купонов, история выплат, прогноз на 12 месяцев',
+    ),
+    (
+      path: '/rebalance',
+      icon: Icons.balance,
+      title: 'Ребалансировка',
+      subtitle: 'Целевые веса портфеля и рекомендации, что докупить или продать',
+    ),
+    (
+      path: '/goals',
+      icon: Icons.flag_outlined,
+      title: 'Цели',
+      subtitle: 'Накопительные цели и прогноз их достижения по текущему тренду',
+    ),
+    (
+      path: '/tax',
+      icon: Icons.receipt_long_outlined,
+      title: 'Налоги',
+      subtitle: 'Оценка налога за год и лоты с датой ЛДВ — для сверки со справкой брокера',
+    ),
+  ];
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(title: const Text('Аналитика')),
+      body: ListView(
+        padding: const EdgeInsets.all(16),
+        children: [
+          for (final e in _entries)
+            Card(
+              child: ListTile(
+                leading: Icon(e.icon),
+                title: Text(e.title),
+                subtitle: Text(e.subtitle),
+                trailing: const Icon(Icons.chevron_right),
+                onTap: () => context.go(e.path),
+              ),
+            ),
+          const SizedBox(height: 12),
+          Text(
+            'Сравнение с бенчмарками живёт на экране «Портфель»: обгон индекса — '
+            'свойство портфеля, а не отдельная тема.',
+            style: Theme.of(context).textTheme.bodySmall,
+          ),
+        ],
+      ),
+    );
+  }
+}

app/lib/features/shell/app_shell.dart

@@ -2,18 +2,46 @@ import 'package:flutter/material.dart';
 import 'package:go_router/go_router.dart';
 
 class _Destination {
-  const _Destination(this.path, this.icon, this.selectedIcon, this.label);
+  const _Destination(this.path, this.icon, this.selectedIcon, this.label,
+      {this.alsoMatches = const [], this.primary = false});
   final String path;
   final IconData icon;
   final IconData selectedIcon;
   final String label;
+
+  /// Extra route prefixes that belong to this destination but do not start with [path] —
+  /// `/instruments/pending` is reached from Импорт and must keep it highlighted, and the
+  /// four phase-4 screens are reached from Аналитика the same way.
+  final List<String> alsoMatches;
+
+  /// Shown directly in the bottom bar on a phone. Everything else moves behind «Ещё».
+  final bool primary;
+
+  /// The longest prefix of [location] this destination claims, or -1 for no match.
+  int matchLength(String location) {
+    var best = -1;
+    for (final p in [path, ...alsoMatches]) {
+      final hit = p == '/' ? location == '/' : location.startsWith(p);
+      if (hit && p.length > best) best = p.length;
+    }
+    return best;
+  }
 }
 
 const _destinations = [
-  _Destination('/', Icons.dashboard_outlined, Icons.dashboard, 'Обзор'),
-  _Destination('/accounts', Icons.account_balance_outlined, Icons.account_balance, 'Счета'),
-  _Destination('/portfolio', Icons.pie_chart_outline, Icons.pie_chart, 'Портфель'),
+  _Destination('/', Icons.dashboard_outlined, Icons.dashboard, 'Обзор', primary: true),
+  _Destination('/accounts', Icons.account_balance_outlined, Icons.account_balance, 'Счета',
+      primary: true),
+  _Destination('/portfolio', Icons.pie_chart_outline, Icons.pie_chart, 'Портфель',
+      primary: true),
+  // One entry for the four phase-4 screens. They keep their own top-level routes from the
+  // contract and stay deep-linkable; the hub at `/analytics` is what the bottom bar and the
+  // rail point at, and `alsoMatches` keeps it highlighted while you are inside any of them.
+  _Destination('/analytics', Icons.insights_outlined, Icons.insights, 'Аналитика',
+      alsoMatches: ['/income', '/rebalance', '/goals', '/tax'], primary: true),
   _Destination('/events', Icons.event_note_outlined, Icons.event_note, 'События'),
+  _Destination('/imports', Icons.upload_file_outlined, Icons.upload_file, 'Импорт',
+      alsoMatches: ['/instruments/pending']),
   _Destination('/cashflow', Icons.swap_horiz_outlined, Icons.swap_horiz, 'Потоки'),
   _Destination('/categories', Icons.category_outlined, Icons.category, 'Категории'),
   _Destination(
@@ -31,6 +59,10 @@ const _wideBreakpoint = 1200.0;
 /// Adaptive navigation shell around the current route: a bottom
 /// [NavigationBar] on narrow surfaces, a [NavigationRail] (collapsed or
 /// extended) otherwise.
+///
+/// The rail shows every destination. The bottom bar shows the four primary ones plus
+/// «Ещё», which opens the rest in a sheet: twelve destinations in a phone-width bar would
+/// leave about 30 px per label, which is not navigation but decoration.
 class AppShell extends StatelessWidget {
   const AppShell({required this.location, required this.child, super.key});
 
@@ -40,12 +72,15 @@ class AppShell extends StatelessWidget {
   int get _selectedIndex {
     // longest prefix wins, so /portfolio/instrument/311 keeps Портфель selected
     var best = -1;
+    var bestLength = -1;
     for (var i = 0; i < _destinations.length; i++) {
-      final path = _destinations[i].path;
-      final matches = path == '/' ? location == '/' : location.startsWith(path);
-      if (matches && (best == -1 || path.length > _destinations[best].path.length)) best = i;
+      final length = _destinations[i].matchLength(location);
+      if (length > bestLength) {
+        best = i;
+        bestLength = length;
+      }
     }
-    return best == -1 ? 0 : best;
+    return best == -1 || bestLength < 0 ? 0 : best;
   }
 
   void _onSelect(BuildContext context, int index) {
@@ -57,18 +92,36 @@ class AppShell extends StatelessWidget {
     final width = MediaQuery.sizeOf(context).width;
 
     if (width < _narrowBreakpoint) {
+      final primary = _destinations.where((d) => d.primary).toList();
+      final selected = _destinations[_selectedIndex];
+      final primaryIndex = primary.indexOf(selected);
+
       return Scaffold(
         body: SafeArea(child: child),
         bottomNavigationBar: NavigationBar(
-          selectedIndex: _selectedIndex,
-          onDestinationSelected: (i) => _onSelect(context, i),
+          // nothing primary matches ⇒ we are inside a screen that lives behind «Ещё»,
+          // and «Ещё» is what should look active
+          selectedIndex: primaryIndex >= 0 ? primaryIndex : primary.length,
+          onDestinationSelected: (i) {
+            if (i >= primary.length) {
+              _showMore(context, selected);
+            } else {
+              final target = _destinations.indexOf(primary[i]);
+              _onSelect(context, target);
+            }
+          },
           destinations: [
-            for (final d in _destinations)
+            for (final d in primary)
               NavigationDestination(
                 icon: Icon(d.icon),
                 selectedIcon: Icon(d.selectedIcon),
                 label: d.label,
               ),
+            NavigationDestination(
+              icon: const Icon(Icons.more_horiz),
+              selectedIcon: const Icon(Icons.more_horiz),
+              label: primaryIndex >= 0 ? 'Ещё' : selected.label,
+            ),
           ],
         ),
       );
@@ -99,4 +152,31 @@ class AppShell extends StatelessWidget {
       ),
     );
   }
+
+  /// The non-primary destinations, as a sheet. The currently open one is ticked, so «Ещё»
+  /// still answers "where am I".
+  void _showMore(BuildContext context, _Destination current) {
+    showModalBottomSheet<void>(
+      context: context,
+      showDragHandle: true,
+      builder: (sheetContext) => SafeArea(
+        child: ListView(
+          shrinkWrap: true,
+          children: [
+            for (final d in _destinations.where((d) => !d.primary))
+              ListTile(
+                leading: Icon(d == current ? d.selectedIcon : d.icon),
+                title: Text(d.label),
+                selected: d == current,
+                trailing: d == current ? const Icon(Icons.check) : null,
+                onTap: () {
+                  Navigator.of(sheetContext).pop();
+                  if (d != current) context.go(d.path);
+                },
+              ),
+          ],
+        ),
+      ),
+    );
+  }
 }