feat: surface read-only load errors

lib/screens/event_log_screen.dart

@@ -1,6 +1,8 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
+import '../app/load_state.dart';
 import '../providers/providers.dart';
+import '../widgets/load_error_view.dart';
 
 /// Экран просмотра лога событий.
 class EventLogScreen extends ConsumerStatefulWidget {
@@ -11,7 +13,6 @@ class EventLogScreen extends ConsumerStatefulWidget {
 }
 
 class _EventLogScreenState extends ConsumerState<EventLogScreen> {
-  bool _loading = true;
   int _limit = 100;
 
   @override
@@ -21,14 +22,13 @@ class _EventLogScreenState extends ConsumerState<EventLogScreen> {
   }
 
   Future<void> _load() async {
-    setState(() => _loading = true);
     await ref.read(eventLogProvider.notifier).load(limit: _limit);
-    if (mounted) setState(() => _loading = false);
   }
 
   @override
   Widget build(BuildContext context) {
-    final events = ref.watch(eventLogProvider);
+    final eventsState = ref.watch(eventLogProvider);
+    final events = eventsState.data;
 
     return Scaffold(
       appBar: AppBar(
@@ -47,31 +47,68 @@ class _EventLogScreenState extends ConsumerState<EventLogScreen> {
           ),
         ],
       ),
-      body: _loading
-          ? const Center(
-              child: CircularProgressIndicator(color: Colors.deepOrange),
-            )
-          : events.isEmpty
-          ? const Center(
-              child: Text(
-                'Нет событий',
-                style: TextStyle(color: Colors.white54),
-              ),
-            )
-          : RefreshIndicator(
-              color: Colors.deepOrange,
-              onRefresh: _load,
-              child: ListView.builder(
-                padding: const EdgeInsets.all(8),
-                itemCount: events.length,
-                itemBuilder: (context, index) {
-                  final event = events[index];
-                  return _EventRow(
-                    event: event is Map ? Map<String, dynamic>.from(event) : {},
-                  );
-                },
-              ),
-            ),
+      body: _buildContent(eventsState, events),
+    );
+  }
+
+  Widget _buildContent(
+    LoadState<List<dynamic>> eventsState,
+    List<dynamic> events,
+  ) {
+    if ((eventsState.isIdle || eventsState.isLoading) && events.isEmpty) {
+      return const Center(
+        child: CircularProgressIndicator(color: Colors.deepOrange),
+      );
+    }
+
+    if (eventsState.hasError && events.isEmpty) {
+      return LoadErrorView(
+        title: 'Не удалось загрузить лог событий',
+        message: eventsState.errorMessage,
+        icon: Icons.list_alt,
+        onRetry: _load,
+      );
+    }
+
+    if (events.isEmpty) {
+      return const Center(
+        child: Text('Нет событий', style: TextStyle(color: Colors.white54)),
+      );
+    }
+
+    final hasStatusHeader = eventsState.isLoading || eventsState.hasError;
+    final statusHeaderCount = hasStatusHeader ? 1 : 0;
+
+    return RefreshIndicator(
+      color: Colors.deepOrange,
+      onRefresh: _load,
+      child: ListView.builder(
+        physics: const AlwaysScrollableScrollPhysics(),
+        padding: const EdgeInsets.all(8),
+        itemCount: events.length + statusHeaderCount,
+        itemBuilder: (context, index) {
+          if (hasStatusHeader && index == 0) {
+            if (eventsState.isLoading) {
+              return const Padding(
+                padding: EdgeInsets.only(bottom: 12),
+                child: LinearProgressIndicator(color: Colors.deepOrange),
+              );
+            }
+
+            return LoadErrorBanner(
+              title: 'Не удалось обновить лог событий',
+              message: eventsState.errorMessage,
+              onRetry: _load,
+            );
+          }
+
+          final eventIndex = index - statusHeaderCount;
+          final event = events[eventIndex];
+          return _EventRow(
+            event: event is Map ? Map<String, dynamic>.from(event) : {},
+          );
+        },
+      ),
     );
   }
 }