Update lib/model.js

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

Author: mahi656

lib/model.js

@@ -358,11 +358,11 @@ Model.prototype.$__handleSave = function(options, callback) {
   if (this.$isNew) {
     // send entire doc
     let obj;
-    if (this.$__schema.options.minimize === false) {
-      obj = this._doc;
-    } else {
-      obj = this.toObject(saveToObjectOptions);
-    }
+    // Always use toObject for serialization; control minimize via options
+    saveToObjectOptions = Object.assign({}, saveToObjectOptions, {
+      minimize: this.$__schema.options.minimize
+    });
+    obj = this.toObject(saveToObjectOptions);
     if ((obj || {})._id === void 0) {
       // documents must have an _id else mongoose won't know
       // what to update later if more changes are made. the user