look aheead limit defined by user

lib/screens/look_ahead_screen.dart

@@ -7,6 +7,7 @@ import 'package:provider/provider.dart';
 import '../models/bank.dart';
 import '../models/transaction_meta.dart';
 import '../providers/bank_provider.dart';
+import '../providers/preferences_provider.dart';
 import '../providers/tx_meta_provider.dart';
 import '../screens/transaction_detail_screen.dart';
 import '../utils/app_theme.dart';
@@ -37,8 +38,6 @@ class _LookAheadScreenState extends State<LookAheadScreen> {
   List<RecurringItem>? _cachedItems;
   int? _itemsCacheKey;
 
-  static const _maxYearsAhead = 5;
-
   @override
   void initState() {
     super.initState();
@@ -51,11 +50,6 @@ class _LookAheadScreenState extends State<LookAheadScreen> {
 
   DateTime get _minMonth => monthStart(_today);
 
-  DateTime get _maxMonth {
-    final t = _today;
-    return DateTime(t.year + _maxYearsAhead, t.month);
-  }
-
   /// Inclusive end date for the selected period.
   DateTime get _through {
     if (_period == _PeriodMode.yearly) {
@@ -69,50 +63,67 @@ class _LookAheadScreenState extends State<LookAheadScreen> {
     return formatMonthYear(_cursor);
   }
 
-  bool get _canGoBack {
+  DateTime _maxMonthFor(int maxYears) {
+    final t = _today;
+    return DateTime(t.year + maxYears, t.month);
+  }
+
+  bool _canGoBack() {
     if (_period == _PeriodMode.yearly) {
       return _cursor.year > _today.year;
     }
     return monthStart(_cursor).isAfter(_minMonth);
   }
 
-  bool get _canGoForward {
+  bool _canGoForward(int maxYears) {
     if (_period == _PeriodMode.yearly) {
-      return _cursor.year < _today.year + _maxYearsAhead;
+      return _cursor.year < _today.year + maxYears;
     }
-    return monthStart(_cursor).isBefore(_maxMonth);
+    return monthStart(_cursor).isBefore(_maxMonthFor(maxYears));
   }
 
-  void _setPeriod(_PeriodMode mode) {
+  void _clampCursor(int maxYears) {
+    if (_period == _PeriodMode.yearly) {
+      if (_cursor.year > _today.year + maxYears) {
+        _cursor = DateTime(_today.year + maxYears);
+      }
+    } else {
+      final maxMonth = _maxMonthFor(maxYears);
+      if (_cursor.isAfter(maxMonth)) _cursor = maxMonth;
+    }
+  }
+
+  void _setPeriod(_PeriodMode mode, int maxYears) {
     if (mode == _period) return;
     setState(() {
       _period = mode;
       if (mode == _PeriodMode.yearly) {
         _cursor = DateTime(_cursor.year);
         if (_cursor.year < _today.year) _cursor = DateTime(_today.year);
-        if (_cursor.year > _today.year + _maxYearsAhead) {
-          _cursor = DateTime(_today.year + _maxYearsAhead);
+        if (_cursor.year > _today.year + maxYears) {
+          _cursor = DateTime(_today.year + maxYears);
         }
       } else {
         final month = DateTime(_cursor.year, _today.month);
         _cursor = month.isBefore(_minMonth) ? _minMonth : monthStart(month);
-        if (_cursor.isAfter(_maxMonth)) _cursor = _maxMonth;
+        final maxMonth = _maxMonthFor(maxYears);
+        if (_cursor.isAfter(maxMonth)) _cursor = maxMonth;
       }
     });
   }
 
-  void _go(int delta) {
+  void _go(int delta, int maxYears) {
     setState(() {
       if (_period == _PeriodMode.yearly) {
         final next = DateTime(_cursor.year + delta);
-        if (next.year < _today.year ||
-            next.year > _today.year + _maxYearsAhead) {
+        if (next.year < _today.year || next.year > _today.year + maxYears) {
           return;
         }
         _cursor = next;
       } else {
         final next = addMonths(monthStart(_cursor), delta);
-        if (next.isBefore(_minMonth) || next.isAfter(_maxMonth)) return;
+        final maxMonth = _maxMonthFor(maxYears);
+        if (next.isBefore(_minMonth) || next.isAfter(maxMonth)) return;
         _cursor = next;
       }
     });
@@ -131,6 +142,18 @@ class _LookAheadScreenState extends State<LookAheadScreen> {
   Widget _buildContent(BuildContext context) {
     final bank = context.watch<BankController>();
     final meta = context.watch<TxMetaController>();
+    final maxYears =
+        context.watch<PreferencesController>().lookAheadMaxYears;
+    final maxMonth = _maxMonthFor(maxYears);
+    final needsClamp = _period == _PeriodMode.yearly
+        ? _cursor.year > _today.year + maxYears
+        : _cursor.isAfter(maxMonth);
+    if (needsClamp) {
+      WidgetsBinding.instance.addPostFrameCallback((_) {
+        if (!mounted) return;
+        setState(() => _clampCursor(maxYears));
+      });
+    }
     final theme = Theme.of(context);
     final colors = theme.colorScheme;
 
@@ -202,15 +225,15 @@ class _LookAheadScreenState extends State<LookAheadScreen> {
           children: [
             _PeriodToolbar(
               period: _period,
-              onPeriodChanged: _setPeriod,
+              onPeriodChanged: (mode) => _setPeriod(mode, maxYears),
             ),
             const SizedBox(height: 10),
             _PeriodNavigator(
               title: _periodTitle,
-              canGoBack: _canGoBack,
-              canGoForward: _canGoForward,
-              onBack: () => _go(-1),
-              onForward: () => _go(1),
+              canGoBack: _canGoBack(),
+              canGoForward: _canGoForward(maxYears),
+              onBack: () => _go(-1, maxYears),
+              onForward: () => _go(1, maxYears),
               backTooltip:
                   _period == _PeriodMode.yearly ? 'Previous year' : 'Previous month',
               forwardTooltip: