feat(crash): add app version and device info to crash reports

Issue reports now include:
- App version (from package_info_plus)
- OS name and version (non-personal, from dart:io Platform)
- Error and stack trace wrapped in triple-backtick code blocks
  so Codeberg renders them as preformatted text

Closes #59

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

lib/ui/screens/crash_screen.dart

@@ -1,5 +1,8 @@
+import 'dart:io';
+
 import 'package:flutter/material.dart';
 import 'package:flutter/services.dart';
+import 'package:package_info_plus/package_info_plus.dart';
 import 'package:url_launcher/url_launcher.dart';
 
 class CrashScreen extends StatelessWidget {
@@ -12,6 +15,20 @@ class CrashScreen extends StatelessWidget {
   final Object exception;
   final StackTrace? stackTrace;
 
+  Future<String> _buildReport() async {
+    String version = 'unknown';
+    try {
+      final info = await PackageInfo.fromPlatform();
+      version = '${info.version}+${info.buildNumber}';
+    } catch (_) {}
+    final platform =
+        '${Platform.operatingSystem} ${Platform.operatingSystemVersion}';
+    return 'App Version: $version\n'
+        'Platform: $platform\n\n'
+        'Error:\n```\n$exception\n```\n\n'
+        'Stack Trace:\n```\n$stackTrace\n```';
+  }
+
   @override
   Widget build(BuildContext context) {
     return MaterialApp(
@@ -74,7 +91,7 @@ class CrashScreen extends StatelessWidget {
               const SizedBox(height: 24),
               FilledButton.icon(
                 onPressed: () async {
-                  final data = 'Error: $exception\n\nStack Trace:\n$stackTrace';
+                  final data = await _buildReport();
                   await Clipboard.setData(ClipboardData(text: data));
                   if (context.mounted) {
                     ScaffoldMessenger.of(context).showSnackBar(
@@ -91,12 +108,11 @@ class CrashScreen extends StatelessWidget {
               const SizedBox(height: 16),
               OutlinedButton.icon(
                 onPressed: () async {
+                  final report = await _buildReport();
                   final title = Uri.encodeComponent(
                     'Crash: ${exception.toString().split('\n').first}',
                   );
-                  final body = Uri.encodeComponent(
-                    'Error: $exception\n\nStack Trace:\n$stackTrace',
-                  );
+                  final body = Uri.encodeComponent(report);
                   final url = Uri.parse(
                     'https://codeberg.org/guettli/sharedinbox/issues/new?title=$title&body=$body',
                   );
@@ -115,9 +131,7 @@ class CrashScreen extends StatelessWidget {
                     }
                   } catch (e) {
                     if (context.mounted) {
-                      ScaffoldMessenger.of(
-                        context,
-                      ).showSnackBar(
+                      ScaffoldMessenger.of(context).showSnackBar(
                         SnackBar(
                           duration: const Duration(seconds: 5),
                           content: Text('Error: $e'),

pubspec.yaml

@@ -49,6 +49,9 @@ dependencies:
   flutter_local_notifications: ^18.0.1
   workmanager: ^0.9.0
 
+  # App version metadata for crash reports
+  package_info_plus: ^8.0.0
+
 dev_dependencies:
   flutter_test:
     sdk: flutter

test/widget/crash_screen_test.dart

@@ -1,6 +1,7 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_test/flutter_test.dart';
 import 'package:mockito/mockito.dart';
+import 'package:package_info_plus/package_info_plus.dart';
 import 'package:plugin_platform_interface/plugin_platform_interface.dart';
 import 'package:sharedinbox/ui/screens/crash_screen.dart';
 import 'package:url_launcher_platform_interface/url_launcher_platform_interface.dart';
@@ -23,6 +24,16 @@ class MockUrlLauncher extends Mock
 }
 
 void main() {
+  setUpAll(() {
+    PackageInfo.setMockInitialValues(
+      appName: 'SharedInbox',
+      packageName: 'org.sharedinbox',
+      version: '1.0.0',
+      buildNumber: '42',
+      buildSignature: '',
+    );
+  });
+
   testWidgets('CrashScreen shows error details and has a report button', (
     tester,
   ) async {
@@ -56,9 +67,7 @@ void main() {
       mock.launchedUrl,
       contains('title=Crash%3A%20TestException%3A%20something%20broke'),
     );
-    expect(
-      mock.launchedUrl,
-      contains('body=Error%3A%20TestException%3A%20something%20broke'),
-    );
+    expect(mock.launchedUrl, contains('App%20Version%3A%201.0.0%2B42'));
+    expect(mock.launchedUrl, contains('TestException%3A%20something%20broke'));
   });
 }