fix(test): apply dart format and prefer_single_quotes lint fixes

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

test/unit/email_repository_impl_test.dart

@@ -296,8 +296,7 @@ void main() {
       expect(archiveEmail, isNotNull);
       expect(archiveEmail!.mailboxPath, 'Archive');
 
-      final inboxEmails =
+      final inboxEmails = await r.emails.observeEmails('acc-1', 'INBOX').first;
-          await r.emails.observeEmails('acc-1', 'INBOX').first;
       expect(inboxEmails, hasLength(1));
       expect(inboxEmails.first.id, 'acc-1:INBOX:50');
 

test/unit/migration_test.dart

@@ -536,16 +536,16 @@ void main() {
       // Two emails with the same UID but in different mailboxes — old format.
       final now = DateTime.now().millisecondsSinceEpoch ~/ 1000;
       rawDb.execute(
-        "INSERT INTO emails (id, account_id, mailbox_path, uid, received_at, thread_id) "
+        'INSERT INTO emails (id, account_id, mailbox_path, uid, received_at, thread_id) '
         "VALUES ('acc-1:50', 'acc-1', 'INBOX', 50, $now, 'acc-1:50')",
       );
       rawDb.execute(
-        "INSERT INTO emails (id, account_id, mailbox_path, uid, received_at) "
+        'INSERT INTO emails (id, account_id, mailbox_path, uid, received_at) '
         "VALUES ('acc-1:50-arch', 'acc-1', 'Archive', 50, $now)",
       );
       // A third email with a Message-ID-based thread_id (should not be changed).
       rawDb.execute(
-        "INSERT INTO emails (id, account_id, mailbox_path, uid, received_at, thread_id) "
+        'INSERT INTO emails (id, account_id, mailbox_path, uid, received_at, thread_id) '
         "VALUES ('acc-1:99', 'acc-1', 'INBOX', 99, $now, '<original@example.com>')",
       );
 
@@ -556,13 +556,13 @@ void main() {
 
       // Thread for the first email (old-format IDs).
       rawDb.execute(
-        "INSERT INTO threads (account_id, mailbox_path, id, latest_date, latest_email_id, email_ids_json) "
+        'INSERT INTO threads (account_id, mailbox_path, id, latest_date, latest_email_id, email_ids_json) '
         "VALUES ('acc-1', 'INBOX', 'acc-1:50', $now, 'acc-1:50', '[\"acc-1:50\"]')",
       );
 
       // A pending change referencing the first email's old ID.
       rawDb.execute(
-        "INSERT INTO pending_changes (account_id, resource_type, resource_id, change_type, payload, created_at) "
+        'INSERT INTO pending_changes (account_id, resource_type, resource_id, change_type, payload, created_at) '
         "VALUES ('acc-1', 'Email', 'acc-1:50', 'flag_seen', '{\"seen\":true}', $now)",
       );
 
@@ -589,8 +589,7 @@ void main() {
       expect(bodyRows.first.emailId, 'acc-1:INBOX:50');
 
       // thread_id where it was the email's own ID should be updated.
-      final inboxEmail =
+      final inboxEmail = emailRows.firstWhere((r) => r.id == 'acc-1:INBOX:50');
-          emailRows.firstWhere((r) => r.id == 'acc-1:INBOX:50');
       expect(inboxEmail.threadId, 'acc-1:INBOX:50');
 
       // thread_id based on a real Message-ID must be left unchanged.