added IMAP, LetsEncrypt, update layout

internal/mailstore/resolve.go

@@ -0,0 +1,17 @@
+package mailstore
+
+import "mailgoserver/internal/db"
+
+// ResolveRecipient looks up a local mailbox for addr — its primary email first, then
+// any active alias — so mail sent to an alias lands in the owning mailbox's INBOX.
+func (s *Store) ResolveRecipient(addr string) (*db.Mailbox, error) {
+	mbox, err := s.DB.GetMailboxByEmail(addr)
+	if err != nil || mbox != nil {
+		return mbox, err
+	}
+	alias, err := s.DB.GetAliasByEmail(addr)
+	if err != nil || alias == nil {
+		return nil, err
+	}
+	return s.DB.GetMailboxByID(alias.MailboxID)
+}