Let plugins run their own PHP code

A plugin can now bring a plugin.php that registers hooks, scheduled tasks, its own tables, public pages and admin screens. Failures stay contained to the plugin; a form on a plugin page can be submitted.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/Controller/FormController.php

@@ -9,6 +9,7 @@ use App\Content\PageRepository;
 use App\Content\SiteSettings;
 use App\Content\Turnstile;
 use App\Ops\MailCheck;
+use App\Plugin\PluginRuntime;
 use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;
 use Symfony\Component\HttpFoundation\Request;
 use Symfony\Component\HttpFoundation\Response;
@@ -33,6 +34,7 @@ final class FormController extends AbstractController
         private string $secret,
         private string $siteOrigin,
         private Languages $languages,
+        private PluginRuntime $plugins,
     ) {
     }
 
@@ -41,7 +43,8 @@ final class FormController extends AbstractController
     {
         $form = $this->forms->findBySlug($slug);
         $path = trim($request->request->getString('page'), '/') ?: $this->settings->homePath();
-        $page = $this->pages->findPublished($path);
+        // Ein Formular kann auch auf der Seite eines Plugins stehen (ADR 127).
+        $page = $this->pages->findPublished($path) ?? $this->plugins->page('/'.$path);
         if (null === $form || null === $page) {
             throw $this->createNotFoundException('Formular oder Seite nicht gefunden.');
         }
@@ -77,8 +80,11 @@ final class FormController extends AbstractController
             return $this->renderPage($request, $page, $form, ['errors' => ['_form' => 'Gerade gehen sehr viele Anfragen ein. Bitte versuchen Sie es später erneut oder melden Sie sich telefonisch.'], 'values' => $checked['values']], null === $language ? null : ($page['path'] === $this->settings->homePath() ? $language : $language.'/'.$translatedPath));
         }
         if (!$silentlyDropped) {
+            // Angaben eines Plugins zur Seite, von der die Anfrage kommt: Name => Text.
+            $extra = array_filter((array) $this->plugins->applyFilters('form.context', [], $form, $path), 'is_string');
+            $checked['values'] += $extra;
             $submission = $this->forms->store($form['id'], $checked['values'], $checked['consent'], $senderHash);
-            if ($this->deliver($form, $checked['values'])) {
+            if ($this->deliver($form, $checked['values'], $extra)) {
                 $this->forms->markDelivered($submission);
             }
         }
@@ -101,9 +107,12 @@ final class FormController extends AbstractController
         return $age >= FormRepository::MIN_SECONDS && $age <= FormRepository::MAX_SECONDS;
     }
 
-    private function deliver(array $form, array $values): bool
+    private function deliver(array $form, array $values, array $extra = []): bool
     {
         $lines = [];
+        foreach ($extra as $name => $text) {
+            $lines[] = $name.': '.$text;
+        }
         foreach ($form['fields'] as $field) {
             // Ein Schritt ist eine Überschrift in der Post; ein Feld, das nicht galt, bleibt weg.
             if ('step' === $field['type']) {