[FEATURE] Add PSR-14 Event after form is built (#6286)

Resolves: TYPO3-Documentation/Changelog-To-Doc#1394
Releases: main

Author: sarahmccarthy123

Documentation/ApiOverview/Events/Events/Form/AfterFormIsBuiltEvent.rst

@@ -0,0 +1,33 @@
+..  include:: /Includes.rst.txt
+..  index:: Events; AfterFormIsBuiltEvent
+
+..  _AfterFormIsBuiltEvent:
+
+=====================
+AfterFormIsBuiltEvent
+=====================
+
+..  versionadded:: 14.0
+    The events :php-short:`TYPO3\CMS\Form\Event\AfterFormIsBuiltEvent`
+    and :php-short:`TYPO3\CMS\Form\Event\BeforeRenderableIsAddedToFormEvent`
+    provide an improved replacement for the removed hook
+    :php:`$GLOBALS['TYPO3_CONF_VARS']['SC_OPTIONS']['ext/form']['afterBuildingFinished']`.
+
+The event :php-short:`TYPO3\CMS\Form\Event\AfterFormIsBuiltEvent`
+allows the form definition to be modified after a form has been created.
+
+
+..  _AfterFormIsBuiltEvent-example:
+
+Example
+=======
+
+..  literalinclude:: _AfterFormIsBuiltEvent/_MyEventListener.php
+    :caption: EXT:my_extension/Classes/EventListener/MyEventListener.php
+
+..  _AfterFormIsBuiltEvent-api:
+
+API
+===
+
+..  include:: /CodeSnippets/Events/Form/AfterFormIsBuiltEvent.rst.txt

Documentation/ApiOverview/Events/Events/Form/_AfterFormIsBuiltEvent/_MyEventListener.php

@@ -0,0 +1,19 @@
+<?php
+
+declare(strict_types=1);
+
+namespace MyVendor\MyExtension\EventListener;
+
+use TYPO3\CMS\Core\Attribute\AsEventListener;
+use TYPO3\CMS\Form\Event\AfterFormIsBuiltEvent;
+
+final readonly class MyEventListener
+{
+    #[AsEventListener(
+        identifier: 'my-extension/after-form-is-built',
+    )]
+    public function __invoke(AfterFormIsBuiltEvent $event): void
+    {
+        $event->form->setLabel('foo');
+    }
+}

Documentation/CodeSnippets/Config/Api/Events/EventsForm.php

@@ -1,6 +1,12 @@
 <?php
 
 return [
+    [
+        'action' => 'createPhpClassDocs',
+        'class' => \TYPO3\CMS\Form\Event\AfterFormIsBuiltEvent::class,
+        'targetFileName' => 'CodeSnippets/Events/Form/AfterFormIsBuiltEvent.rst.txt',
+        'withCode' => false,
+    ],
     [
         'action' => 'createPhpClassDocs',
         'class' => \TYPO3\CMS\Form\Mvc\Persistence\Event\AfterFormDefinitionLoadedEvent::class,

Documentation/CodeSnippets/Events/Form/AfterFormIsBuiltEvent.rst.txt

@@ -0,0 +1,10 @@
+..  Generated by https://github.com/TYPO3-Documentation/t3docs-codesnippets
+..  php:namespace::  TYPO3\CMS\Form\Event
+
+..  php:class:: AfterFormIsBuiltEvent
+
+    Listeners to this event will be able to modify the form definition
+    after a form is created.
+
+    ..  php:attr:: form
+        :public: