docs: add missing $allowEmptyInserts

Author: kenjis

user_guide_src/source/models/model.rst

@@ -157,6 +157,17 @@ potential mass assignment vulnerabilities.
 
 .. note:: The `$primaryKey`_ field should never be an allowed field.
 
+$allowEmptyInserts
+------------------
+
+.. versionadded:: 4.3.0
+
+Whether to allow inserting empty data. The default value is ``false``, meaning
+that if you try to insert empty data, an exception with
+"There is no data to insert." will raise.
+
+You may also change this setting with the :ref:`model-allow-empty-inserts` method.
+
 Dates
 -----
 
@@ -371,6 +382,8 @@ You can use ``allowEmptyInserts()`` method to insert empty data. The Model throw
 
 .. literalinclude:: model/056.php
 
+You may also change this setting with the `$allowEmptyInserts`_ property.
+
 You can enable the check again by calling ``allowEmptyInserts(false)``.
 
 update()

user_guide_src/source/models/model/005.php

@@ -16,6 +16,8 @@ class UserModel extends Model
 
     protected $allowedFields = ['name', 'email'];
 
+    protected bool $allowEmptyInserts = false;
+
     // Dates
     protected $useTimestamps = false;
     protected $dateFormat    = 'datetime';