refactor: unify mail display with shared ThreadTile widget (#445)

lib/ui/screens/email_list_screen.dart

@@ -13,9 +13,9 @@ import 'package:sharedinbox/core/repositories/email_repository.dart';
 import 'package:sharedinbox/di.dart';
 import 'package:sharedinbox/ui/screens/email_action_helpers.dart';
 import 'package:sharedinbox/ui/widgets/email_thread_tile.dart';
-import 'package:sharedinbox/ui/widgets/email_tile.dart';
 import 'package:sharedinbox/ui/widgets/folder_drawer.dart';
 import 'package:sharedinbox/ui/widgets/snooze_picker.dart';
+import 'package:sharedinbox/ui/widgets/thread_tile.dart';
 
 class EmailListScreen extends ConsumerStatefulWidget {
   const EmailListScreen({
@@ -762,9 +762,10 @@ class _EmailListScreenState extends ConsumerState<EmailListScreen> {
       itemCount: emails.length,
       itemBuilder: (ctx, i) {
         final e = emails[i];
+        final t = EmailThread.fromEmail(e);
         final isSelected = _selectedSearchIds.contains(e.id);
-        return EmailTile(
-          email: e,
+        return ThreadTile(
+          thread: t,
           selected: isSelected,
           leading: SizedBox(
             width: 40,

lib/ui/screens/search_screen.dart

@@ -8,7 +8,7 @@ import 'package:sharedinbox/core/models/email.dart';
 import 'package:sharedinbox/core/models/mailbox.dart';
 import 'package:sharedinbox/core/utils/logger.dart';
 import 'package:sharedinbox/di.dart';
-import 'package:sharedinbox/ui/widgets/email_tile.dart';
+import 'package:sharedinbox/ui/widgets/thread_tile.dart';
 
 final _searchHistoryProvider = FutureProvider.autoDispose<List<String>>((
   ref,
@@ -189,9 +189,9 @@ class _SearchScreenState extends ConsumerState<SearchScreen> {
         if (r.emails.isNotEmpty) ...[
           const _SectionHeader('Messages'),
           for (final e in r.emails)
-            EmailTile(
-              email: e,
-              showLocation: true,
+            ThreadTile(
+              thread: EmailThread.fromEmail(e),
+              locationLabel: '${e.accountId} • ${e.mailboxPath}',
               onTap: () => context.push(
                 '/accounts/${e.accountId}/mailboxes'
                 '/${Uri.encodeComponent(e.mailboxPath)}'

lib/ui/widgets/thread_tile.dart

@@ -0,0 +1,121 @@
+import 'package:flutter/material.dart';
+import 'package:intl/intl.dart';
+
+import 'package:sharedinbox/core/models/email.dart';
+
+final _dateFmt = DateFormat('MMM d');
+// Cache formatted dates by local calendar day to avoid repeated DateFormat.format calls.
+final _formattedDates = <int, String>{};
+
+int _dayKey(DateTime dt) => dt.year * 10000 + dt.month * 100 + dt.day;
+
+String _fmtDate(DateTime dt) =>
+    _formattedDates[_dayKey(dt)] ??= _dateFmt.format(dt);
+
+/// A list tile for an [EmailThread].
+///
+/// Used in inbox lists, combined inbox, and search result lists.
+/// Pass a custom [leading] widget to support selection-mode checkboxes.
+/// Pass [locationLabel] to show an extra subtitle line (e.g. account name or
+/// "accountId • mailboxPath") — useful in cross-mailbox views.
+class ThreadTile extends StatelessWidget {
+  const ThreadTile({
+    super.key,
+    required this.thread,
+    required this.onTap,
+    this.leading,
+    this.selected = false,
+    this.onLongPress,
+    this.locationLabel,
+  });
+
+  final EmailThread thread;
+  final VoidCallback onTap;
+  final Widget? leading;
+  final bool selected;
+  final VoidCallback? onLongPress;
+
+  /// When non-null, appended as an extra subtitle line in primary colour.
+  final String? locationLabel;
+
+  @override
+  Widget build(BuildContext context) {
+    final senderNames = thread.participants.isEmpty
+        ? '(unknown)'
+        : thread.participants.map((a) => a.name ?? a.email).take(3).join(', ');
+
+    return ListTile(
+      leading: leading ??
+          Icon(
+            thread.hasUnread ? Icons.mail : Icons.mail_outline,
+            color:
+                thread.hasUnread ? Theme.of(context).colorScheme.primary : null,
+          ),
+      title: Row(
+        children: [
+          Expanded(
+            child: Text(
+              senderNames,
+              style: thread.hasUnread
+                  ? const TextStyle(fontWeight: FontWeight.bold)
+                  : null,
+              overflow: TextOverflow.ellipsis,
+            ),
+          ),
+          if (thread.messageCount > 1)
+            Padding(
+              padding: const EdgeInsets.only(left: 4),
+              child: Text(
+                '[${thread.messageCount}]',
+                style: Theme.of(context).textTheme.bodySmall,
+              ),
+            ),
+        ],
+      ),
+      subtitle: Column(
+        crossAxisAlignment: CrossAxisAlignment.start,
+        children: [
+          Text(
+            thread.subject ?? '(no subject)',
+            maxLines: 1,
+            overflow: TextOverflow.ellipsis,
+            style: thread.hasUnread
+                ? const TextStyle(fontWeight: FontWeight.bold)
+                : null,
+          ),
+          if (thread.preview != null && thread.preview!.isNotEmpty)
+            Text(
+              thread.preview!,
+              maxLines: 1,
+              overflow: TextOverflow.ellipsis,
+              style: Theme.of(context).textTheme.bodySmall,
+            ),
+          if (locationLabel != null)
+            Text(
+              locationLabel!,
+              maxLines: 1,
+              overflow: TextOverflow.ellipsis,
+              style: Theme.of(context).textTheme.bodySmall?.copyWith(
+                    color: Theme.of(context).colorScheme.primary,
+                  ),
+            ),
+        ],
+      ),
+      trailing: Row(
+        mainAxisSize: MainAxisSize.min,
+        children: [
+          if (thread.isFlagged)
+            const Icon(Icons.star, color: Colors.amber, size: 16),
+          const SizedBox(width: 4),
+          Text(
+            _fmtDate(thread.latestDate),
+            style: Theme.of(context).textTheme.bodySmall,
+          ),
+        ],
+      ),
+      selected: selected,
+      onTap: onTap,
+      onLongPress: onLongPress,
+    );
+  }
+}