feat: show dish recognition result as bottom sheet on home screen

Remove "Определить блюдо" from ScanScreen and the /scan/dish route.
The + button on each meal card now triggers dish recognition inline —
picks image, shows loading dialog, then presents DishResultSheet as a
modal bottom sheet. After adding to diary the sheet closes and the user
stays on home.

Also fix Navigator.pop crash: showDialog uses the root navigator by
default, so capture Navigator.of(context, rootNavigator: true) before
the async gap and use it to close the loading dialog.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

client/lib/features/scan/dish_result_screen.dart

@@ -1,30 +1,31 @@
 import 'package:flutter/material.dart';
 import 'package:flutter/services.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
-import 'package:go_router/go_router.dart';
 
 import '../../features/menu/menu_provider.dart';
 import '../../features/home/home_provider.dart';
 import '../../shared/models/meal_type.dart';
 import 'recognition_service.dart';
 
-/// Shows the recognition candidates and lets the user confirm a dish entry
-/// before adding it to the diary.
-class DishResultScreen extends ConsumerStatefulWidget {
-  const DishResultScreen({
+/// Bottom sheet that shows dish recognition candidates and lets the user
+/// confirm a dish entry before adding it to the diary.
+class DishResultSheet extends ConsumerStatefulWidget {
+  const DishResultSheet({
     super.key,
     required this.dish,
+    required this.onAdded,
     this.preselectedMealType,
   });
 
   final DishResult dish;
+  final VoidCallback onAdded;
   final String? preselectedMealType;
 
   @override
-  ConsumerState<DishResultScreen> createState() => _DishResultScreenState();
+  ConsumerState<DishResultSheet> createState() => _DishResultSheetState();
 }
 
-class _DishResultScreenState extends ConsumerState<DishResultScreen> {
+class _DishResultSheetState extends ConsumerState<DishResultSheet> {
   late int _selectedIndex;
   late int _portionGrams;
   late String _mealType;
@@ -106,7 +107,7 @@ class _DishResultScreenState extends ConsumerState<DishResultScreen> {
         'portion_g': _portionGrams,
         'source': 'recognition',
       });
-      if (mounted) context.go('/home');
+      if (mounted) widget.onAdded();
     } catch (addError) {
       debugPrint('Add to diary error: $addError');
       if (mounted) {
@@ -123,82 +124,112 @@ class _DishResultScreenState extends ConsumerState<DishResultScreen> {
     final theme = Theme.of(context);
     final hasCandidates = widget.dish.candidates.isNotEmpty;
 
-    return Scaffold(
-      appBar: AppBar(title: const Text('Распознано блюдо')),
-      bottomNavigationBar: hasCandidates
-          ? SafeArea(
-              child: Padding(
-                padding: const EdgeInsets.fromLTRB(20, 8, 20, 16),
-                child: FilledButton(
-                  onPressed: _saving ? null : _addToDiary,
-                  child: _saving
-                      ? const SizedBox(
-                          height: 20,
-                          width: 20,
-                          child: CircularProgressIndicator(strokeWidth: 2),
-                        )
-                      : const Text('Добавить в журнал'),
-                ),
+    return Column(
+      children: [
+        // Drag handle
+        Center(
+          child: Container(
+            width: 40,
+            height: 4,
+            margin: const EdgeInsets.symmetric(vertical: 12),
+            decoration: BoxDecoration(
+              color: theme.colorScheme.onSurfaceVariant.withValues(alpha: 0.4),
+              borderRadius: BorderRadius.circular(2),
+            ),
+          ),
+        ),
+        // Title row
+        Padding(
+          padding: const EdgeInsets.fromLTRB(20, 0, 8, 0),
+          child: Row(
+            children: [
+              Text('Распознано блюдо', style: theme.textTheme.titleMedium),
+              const Spacer(),
+              IconButton(
+                icon: const Icon(Icons.close),
+                onPressed: () => Navigator.pop(context),
               ),
-            )
-          : null,
-      body: hasCandidates
-          ? ListView(
-              padding: const EdgeInsets.all(20),
-              children: [
-                _CandidatesSection(
-                  candidates: widget.dish.candidates,
-                  selectedIndex: _selectedIndex,
-                  onSelect: _selectCandidate,
-                ),
-                const SizedBox(height: 20),
-                _NutritionCard(
-                  calories: _scale(_selected.calories),
-                  proteinG: _scale(_selected.proteinG),
-                  fatG:     _scale(_selected.fatG),
-                  carbsG:   _scale(_selected.carbsG),
-                ),
-                const SizedBox(height: 8),
-                Text(
-                  'КБЖУ приблизительные — определены по фото.',
-                  style: theme.textTheme.bodySmall?.copyWith(
-                    color: theme.colorScheme.onSurfaceVariant,
+            ],
+          ),
+        ),
+        // Scrollable content
+        Expanded(
+          child: hasCandidates
+              ? ListView(
+                  padding: const EdgeInsets.all(20),
+                  children: [
+                    _CandidatesSection(
+                      candidates: widget.dish.candidates,
+                      selectedIndex: _selectedIndex,
+                      onSelect: _selectCandidate,
+                    ),
+                    const SizedBox(height: 20),
+                    _NutritionCard(
+                      calories: _scale(_selected.calories),
+                      proteinG: _scale(_selected.proteinG),
+                      fatG: _scale(_selected.fatG),
+                      carbsG: _scale(_selected.carbsG),
+                    ),
+                    const SizedBox(height: 8),
+                    Text(
+                      'КБЖУ приблизительные — определены по фото.',
+                      style: theme.textTheme.bodySmall?.copyWith(
+                        color: theme.colorScheme.onSurfaceVariant,
+                      ),
+                      textAlign: TextAlign.center,
+                    ),
+                    const SizedBox(height: 20),
+                    _PortionRow(
+                      controller: _portionController,
+                      onMinus: () => _adjustPortion(-10),
+                      onPlus: () => _adjustPortion(10),
+                      onChanged: _onPortionEdited,
+                    ),
+                    const SizedBox(height: 20),
+                    _MealTypeDropdown(
+                      selected: _mealType,
+                      onChanged: (value) {
+                        if (value != null) setState(() => _mealType = value);
+                      },
+                    ),
+                    const SizedBox(height: 16),
+                  ],
+                )
+              : Center(
+                  child: Column(
+                    mainAxisSize: MainAxisSize.min,
+                    children: [
+                      Text(
+                        'Блюдо не распознано',
+                        style: theme.textTheme.titleMedium,
+                      ),
+                      const SizedBox(height: 8),
+                      FilledButton(
+                        onPressed: () => Navigator.pop(context),
+                        child: const Text('Попробовать снова'),
+                      ),
+                    ],
                   ),
-                  textAlign: TextAlign.center,
                 ),
-                const SizedBox(height: 20),
-                _PortionRow(
-                  controller: _portionController,
-                  onMinus: () => _adjustPortion(-10),
-                  onPlus:  () => _adjustPortion(10),
-                  onChanged: _onPortionEdited,
-                ),
-                const SizedBox(height: 20),
-                _MealTypeDropdown(
-                  selected: _mealType,
-                  onChanged: (value) {
-                    if (value != null) setState(() => _mealType = value);
-                  },
-                ),
-                const SizedBox(height: 16),
-              ],
-            )
-          : Center(
-              child: Column(
-                mainAxisSize: MainAxisSize.min,
-                children: [
-                  Text(
-                    'Блюдо не распознано',
-                    style: theme.textTheme.titleMedium,
-                  ),
-                  const SizedBox(height: 8),
-                  FilledButton(
-                    onPressed: () => context.pop(),
-                    child: const Text('Попробовать снова'),
-                  ),
-                ],
+        ),
+        // Bottom button
+        if (hasCandidates)
+          SafeArea(
+            child: Padding(
+              padding: const EdgeInsets.fromLTRB(20, 8, 20, 16),
+              child: FilledButton(
+                onPressed: _saving ? null : _addToDiary,
+                child: _saving
+                    ? const SizedBox(
+                        height: 20,
+                        width: 20,
+                        child: CircularProgressIndicator(strokeWidth: 2),
+                      )
+                    : const Text('Добавить в журнал'),
               ),
             ),
+          ),
+      ],
     );
   }
 }

client/lib/features/scan/recognition_service.dart

@@ -1,8 +1,10 @@
 import 'dart:convert';
 
+import 'package:flutter_riverpod/flutter_riverpod.dart';
 import 'package:image_picker/image_picker.dart';
 
 import '../../core/api/api_client.dart';
+import '../../core/auth/auth_provider.dart';
 
 // ---------------------------------------------------------------------------
 // Models
@@ -181,3 +183,7 @@ class RecognitionService {
     return {'image_base64': base64Data, 'mime_type': mimeType};
   }
 }
+
+final recognitionServiceProvider = Provider<RecognitionService>((ref) {
+  return RecognitionService(ref.read(apiClientProvider));
+});

client/lib/features/scan/scan_screen.dart

@@ -3,17 +3,9 @@ import 'package:flutter_riverpod/flutter_riverpod.dart';
 import 'package:go_router/go_router.dart';
 import 'package:image_picker/image_picker.dart';
 
-import '../../core/auth/auth_provider.dart';
 import 'recognition_service.dart';
 
-// Provider wired to the shared ApiClient.
-final _recognitionServiceProvider = Provider<RecognitionService>((ref) {
-  return RecognitionService(ref.read(apiClientProvider));
-});
-
 /// Entry screen — lets the user choose how to add products.
-/// If [GoRouterState.extra] is a non-null String, it is treated as a meal type ID
-/// and the screen immediately opens the camera for dish recognition.
 class ScanScreen extends ConsumerStatefulWidget {
   const ScanScreen({super.key});
 
@@ -22,24 +14,6 @@ class ScanScreen extends ConsumerStatefulWidget {
 }
 
 class _ScanScreenState extends ConsumerState<ScanScreen> {
-  bool _autoStarted = false;
-
-  @override
-  void didChangeDependencies() {
-    super.didChangeDependencies();
-    if (_autoStarted) return;
-    final mealType = GoRouterState.of(context).extra as String?;
-    if (mealType != null && mealType.isNotEmpty) {
-      _autoStarted = true;
-      // Defer to avoid calling context navigation during build.
-      WidgetsBinding.instance.addPostFrameCallback((_) {
-        if (mounted) {
-          _pickAndRecognize(context, _Mode.dish, mealType: mealType);
-        }
-      });
-    }
-  }
-
   @override
   Widget build(BuildContext context) {
     return Scaffold(
@@ -68,13 +42,6 @@ class _ScanScreenState extends ConsumerState<ScanScreen> {
             onTap: () => _pickAndRecognize(context, _Mode.products),
           ),
           const SizedBox(height: 16),
-          _ModeCard(
-            emoji: '🍽️',
-            title: 'Определить блюдо',
-            subtitle: 'КБЖУ≈ по фото готового блюда',
-            onTap: () => _pickAndRecognize(context, _Mode.dish),
-          ),
-          const SizedBox(height: 16),
           _ModeCard(
             emoji: '✏️',
             title: 'Добавить вручную',
@@ -88,9 +55,8 @@ class _ScanScreenState extends ConsumerState<ScanScreen> {
 
   Future<void> _pickAndRecognize(
     BuildContext context,
-    _Mode mode, {
-    String? mealType,
-  }) async {
+    _Mode mode,
+  ) async {
     final picker = ImagePicker();
 
     List<XFile> files = [];
@@ -118,7 +84,7 @@ class _ScanScreenState extends ConsumerState<ScanScreen> {
     }
 
     if (!context.mounted) return;
-    final service = ref.read(_recognitionServiceProvider);
+    final service = ref.read(recognitionServiceProvider);
 
     // Show loading overlay while the AI processes.
     showDialog(
@@ -141,12 +107,6 @@ class _ScanScreenState extends ConsumerState<ScanScreen> {
             Navigator.pop(context);
             context.push('/scan/confirm', extra: items);
           }
-        case _Mode.dish:
-          final dish = await service.recognizeDish(files.first);
-          if (context.mounted) {
-            Navigator.pop(context);
-            context.push('/scan/dish', extra: {'dish': dish, 'meal_type': mealType});
-          }
       }
     } catch (recognitionError) {
       debugPrint('Recognition error: $recognitionError');
@@ -189,7 +149,7 @@ class _ScanScreenState extends ConsumerState<ScanScreen> {
 // Mode enum
 // ---------------------------------------------------------------------------
 
-enum _Mode { receipt, products, dish }
+enum _Mode { receipt, products }
 
 // ---------------------------------------------------------------------------
 // Widgets