fix(raw-email): save to Downloads and show size in raw email view (#97)

- Replace getTemporaryDirectory() + OpenFilex.open() with
  getDownloadsDirectory() (fallback to temp) so the .eml file lands in
  the public Downloads folder instead of triggering Android's
  "open with" dialog.
- Show a SnackBar with the saved path after download instead of
  launching a file viewer.
- Display the email size (via fmtSize) at the top of the Raw Email
  dialog, above the scrollable content.
- Add widget test covering the size display in the Raw Email dialog.

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

lib/ui/screens/email_detail_screen.dart

@@ -457,11 +457,29 @@ class _EmailDetailScreenState extends ConsumerState<EmailDetailScreen> {
           title: const Text('Raw Email'),
           content: SizedBox(
             width: double.maxFinite,
-            child: SingleChildScrollView(
-              child: SelectableText(
-                raw,
-                style: const TextStyle(fontFamily: 'monospace', fontSize: 12),
-              ),
+            child: Column(
+              mainAxisSize: MainAxisSize.min,
+              crossAxisAlignment: CrossAxisAlignment.start,
+              children: [
+                Text(
+                  fmtSize(raw.length),
+                  style: Theme.of(ctx).textTheme.bodySmall?.copyWith(
+                        color: Theme.of(ctx).colorScheme.outline,
+                      ),
+                ),
+                const SizedBox(height: 4),
+                Flexible(
+                  child: SingleChildScrollView(
+                    child: SelectableText(
+                      raw,
+                      style: const TextStyle(
+                        fontFamily: 'monospace',
+                        fontSize: 12,
+                      ),
+                    ),
+                  ),
+                ),
+              ],
             ),
           ),
           actions: [
@@ -496,13 +514,23 @@ class _EmailDetailScreenState extends ConsumerState<EmailDetailScreen> {
     String raw,
   ) async {
     try {
-      final dir = await getTemporaryDirectory();
+      Directory dir;
+      try {
+        dir =
+            (await getDownloadsDirectory()) ?? (await getTemporaryDirectory());
+      } catch (_) {
+        dir = await getTemporaryDirectory();
+      }
       final subject = (header?.subject ?? 'email')
           .replaceAll(RegExp(r'[^\w\s-]'), '_')
           .trim();
-      final file = File('${dir.path}/$subject.eml');
+      final filename = '$subject.eml';
+      final file = File('${dir.path}/$filename');
       await file.writeAsString(raw);
-      await OpenFilex.open(file.path);
+      if (!context.mounted) return;
+      ScaffoldMessenger.of(context).showSnackBar(
+        SnackBar(content: Text('Saved $filename to ${dir.path}')),
+      );
     } catch (e) {
       if (!context.mounted) return;
       ScaffoldMessenger.of(

test/widget/email_detail_screen_test.dart

@@ -143,6 +143,41 @@ void main() {
       expect(find.text('report.pdf'), findsOneWidget);
     });
 
+    testWidgets('Show Raw Email dialog shows size of email', (tester) async {
+      // 'A' * 2048 → fmtSize(2048) == '2.0 KB'
+      final rawContent = 'A' * 2048;
+      await tester.pumpWidget(
+        buildApp(
+          initialLocation: '/accounts/acc-1/mailboxes/INBOX/emails/acc-1%3A42',
+          overrides: [
+            accountRepositoryProvider.overrideWithValue(
+              FakeAccountRepository([kTestAccount]),
+            ),
+            mailboxRepositoryProvider
+                .overrideWithValue(FakeMailboxRepository()),
+            emailRepositoryProvider.overrideWithValue(
+              FakeEmailRepository(
+                emailDetail: testEmail(),
+                emailBody:
+                    const EmailBody(emailId: 'acc-1:42', attachments: []),
+                rawRfc822: rawContent,
+              ),
+            ),
+          ],
+        ),
+      );
+      await tester.pumpAndSettle();
+
+      await tester.tap(find.byType(PopupMenuButton<String>));
+      await tester.pumpAndSettle();
+
+      await tester.tap(find.text('Show Raw Email'));
+      await tester.pumpAndSettle();
+
+      expect(find.text('Raw Email'), findsOneWidget);
+      expect(find.text('2.0 KB'), findsOneWidget);
+    });
+
     testWidgets('Show Mail Structure opens dialog with MIME parts', (
       tester,
     ) async {

test/widget/helpers.dart

@@ -147,6 +147,7 @@ class FakeEmailRepository implements EmailRepository {
   final List<Email> _emails;
   final Email? _emailDetail;
   final EmailBody _emailBody;
+  final String _rawRfc822;
 
   final List<Email> _searchResults;
 
@@ -155,9 +156,11 @@ class FakeEmailRepository implements EmailRepository {
     Email? emailDetail,
     EmailBody? emailBody,
     List<Email>? searchResults,
+    String rawRfc822 = '',
   })  : _emails = emails ?? [],
         _emailDetail = emailDetail,
         _searchResults = searchResults ?? [],
+        _rawRfc822 = rawRfc822,
         _emailBody = emailBody ?? const EmailBody(emailId: '', attachments: []);
 
   @override
@@ -261,7 +264,7 @@ class FakeEmailRepository implements EmailRepository {
       '/tmp/${attachment.filename}';
 
   @override
-  Future<String> fetchRawRfc822(String emailId) async => '';
+  Future<String> fetchRawRfc822(String emailId) async => _rawRfc822;
 
   @override
   Future<List<Email>> searchEmails(