fix: Delete user-deleted messages on the server even if they show up on IMAP later

Before, if the user deleted a message too quickly after sending, it was deleted only locally. The
fix is to remember for tombstones that the corresponding message should be deleted on the server
too.

src/sql/migrations.rs

@@ -907,6 +907,15 @@ CREATE INDEX msgs_status_updates_index2 ON msgs_status_updates (uid);
         )
         .await?;
     }
+    if dbversion < 111 {
+        // Whether the message part doesn't need to be stored on the server. If all parts are marked
+        // deleted, a server-side deletion is issued.
+        sql.execute_migration(
+            "ALTER TABLE msgs ADD COLUMN deleted INTEGER NOT NULL DEFAULT 0",
+            111,
+        )
+        .await?;
+    }
 
     if dbversion < 111 {
         sql.execute_migration(