fix(imap): parse STATUS responses with an unquoted mailbox name

lib/src/private/imap/status_parser.dart

@@ -6,7 +6,10 @@ import 'response_parser.dart';
 /// Parses status responses
 class StatusParser extends ResponseParser<Mailbox> {
   /// Creates a new parser
-  StatusParser(this.box) : _regex = RegExp(r'(STATUS "[^"]+?" )(.*)');
+  // Matches both a quoted ("INBOX") and an unquoted atom (INBOX) mailbox
+  // name: servers such as Dovecot return the atom form in STATUS responses.
+  StatusParser(this.box)
+    : _regex = RegExp(r'(STATUS (?:"[^"]+?"|[^ (]+) )(.*)');
 
   /// The current mailbox
   Mailbox box;

test/src/imap/status_parser_test.dart

@@ -3,6 +3,7 @@ import 'package:enough_mail/src/private/imap/all_parsers.dart';
 import 'package:enough_mail/src/private/imap/imap_response.dart';
 import 'package:enough_mail/src/private/imap/imap_response_line.dart';
 import 'package:test/test.dart';
+
 // cSpell:disable
 
 void main() {
@@ -58,4 +59,25 @@ void main() {
     expect(processed, true);
     expect(box.messagesExists, 2);
   });
+
+  test('Status with unquoted atom mailbox name', () {
+    // Dovecot answers `STATUS INBOX (...)` rather than `STATUS "INBOX" (...)`.
+    // The parser used to require the quotes, so the response never matched
+    // and every count stayed at its default of 0.
+    const responseText = 'STATUS INBOX (MESSAGES 231 UNSEEN 5 UIDNEXT 4392)';
+    final details = ImapResponse()..add(ImapResponseLine(responseText));
+    final box = Mailbox(
+      encodedName: 'INBOX',
+      encodedPath: 'INBOX',
+      flags: [MailboxFlag.inbox],
+      pathSeparator: '/',
+    );
+    final parser = StatusParser(box);
+    final response = Response<Mailbox>()..status = ResponseStatus.ok;
+    final processed = parser.parseUntagged(details, response);
+    expect(processed, true);
+    expect(box.messagesExists, 231);
+    expect(box.messagesUnseen, 5);
+    expect(box.uidNext, 4392);
+  });
 }