Initial commit of core farm_notification module.

This simply provides a Notifications tab in the farmOS Settings
menu hierarchy, which other modules can add sub-tabs to.

In the future, we can consider putting general notification
logic here as well.

See: https://github.com/farmOS/farmOS/pull/555#issuecomment-1213047719

modules/core/notification/farm_notification.info.yml

@@ -0,0 +1,5 @@
+name: farmOS Notification
+description: Provides farmOS notification features.
+type: module
+package: farmOS
+core_version_requirement: ^9

modules/core/notification/farm_notification.links.task.yml

@@ -0,0 +1,12 @@
+farm_notification.settings:
+  base_route: farm_settings.settings_page
+  route_name: farm_notification.settings
+  title: 'Notifications'
+  weight: 5
+
+# Provide a default sub tab.
+farm_notification.settings_sub:
+  title: 'Notifications'
+  route_name: farm_notification.settings
+  parent_id: farm_notification.settings
+  weight: -5

modules/core/notification/farm_notification.managed_role_permissions.yml

@@ -0,0 +1,3 @@
+farm_notification:
+  config_permissions:
+    - administer farm notification

modules/core/notification/farm_notification.permissions.yml

@@ -0,0 +1,2 @@
+administer farm notification:
+  title: 'Administer farmOS notifications'

modules/core/notification/farm_notification.routing.yml

@@ -0,0 +1,7 @@
+farm_notification.settings:
+  path: '/farm/settings/notification'
+  defaults:
+    _form: '\Drupal\farm_notification\Form\NotificationSettingsForm'
+    _title: 'Notification settings'
+  requirements:
+    _permission: 'administer farm notification'

modules/core/notification/src/Form/NotificationSettingsForm.php

@@ -0,0 +1,41 @@
+<?php
+
+namespace Drupal\farm_notification\Form;
+
+use Drupal\Core\Form\FormBase;
+use Drupal\Core\Form\FormStateInterface;
+
+/**
+ * Provides a farm_notification settings form.
+ */
+class NotificationSettingsForm extends Formbase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getFormId() {
+    return 'farm_noication_settings';
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildForm(array $form, FormStateinterface $form_state) {
+
+    // Add a placeholder message.
+    $form['placeholder'] = [
+      '#type' => 'markup',
+      '#markup' => $this->t('Select the tab for the type of notification to configure. Notification modules can add additional tabs to this page.'),
+    ];
+
+    return $form;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitForm(array &$form, FormStateInterface $form_state) {
+
+  }
+
+}