introduce DC_IMAP_MESSAGE_MOVED event and try harder to send out MDNs

deltachat-ffi/deltachat.h

@@ -3905,7 +3905,7 @@ int64_t          dc_lot_get_timestamp     (const dc_lot_t* lot);
 #define DC_EVENT_SMTP_MESSAGE_SENT        103
 
 /**
- * Emitted when a message was successfully marked as deleted on the SMTP server.
+ * Emitted when a message was successfully marked as deleted on the IMAP server.
  *
  * @param data1 0
  * @param data2 (const char*) Info string in english language.
@@ -3914,6 +3914,15 @@ int64_t          dc_lot_get_timestamp     (const dc_lot_t* lot);
  */
 #define DC_EVENT_IMAP_MESSAGE_DELETED   104
 
+/**
+ * Emitted when a message was successfully moved on IMAP.
+ *
+ * @param data1 0
+ * @param data2 (const char*) Info string in english language.
+ *     Must not be free()'d or modified and is valid only until the callback returns.
+ * @return 0
+ */
+#define DC_EVENT_IMAP_MESSAGE_MOVED   105
 
 /**
  * The library-user should write a warning string to the log.

deltachat-ffi/src/lib.rs

@@ -126,6 +126,7 @@ impl ContextWrapper {
                     | Event::ImapConnected(msg)
                     | Event::SmtpMessageSent(msg)
                     | Event::ImapMessageDeleted(msg)
+                    | Event::ImapMessageMoved(msg)
                     | Event::Warning(msg)
                     | Event::Error(msg)
                     | Event::ErrorNetwork(msg)