Add periodic donate notifications to dashboard.

config/events.php

@@ -158,6 +158,10 @@ return static function (CallableEventDispatcherInterface $dispatcher) {
         Event\GetNotifications::class,
         App\Notification\Check\ProfilerAdvisorCheck::class
     );
+    $dispatcher->addCallableListener(
+        Event\GetNotifications::class,
+        App\Notification\Check\DonateAdvisorCheck::class
+    );
     $dispatcher->addCallableListener(
         Event\GetNotifications::class,
         App\Notification\Check\ServiceCheck::class

src/Notification/Check/DonateAdvisorCheck.php

@@ -0,0 +1,41 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Notification\Check;
+
+use App\Container\EnvironmentAwareTrait;
+use App\Entity\Api\Notification;
+use App\Event\GetNotifications;
+use App\Exception\RateLimitExceededException;
+use App\Session\FlashLevels;
+
+final class DonateAdvisorCheck
+{
+    use EnvironmentAwareTrait;
+
+    public function __invoke(GetNotifications $event): void
+    {
+        $request = $event->getRequest();
+
+        $rateLimit = $request->getRateLimit();
+        try {
+            $rateLimit->checkRequestRateLimit($request, 'notification:donate', 600, 1);
+        } catch (RateLimitExceededException) {
+            return;
+        }
+
+        $notification = new Notification();
+        $notification->title = __('AzuraCast is free and open-source software.');
+        $notification->body = __(
+            'If you are enjoying AzuraCast, please consider donating to support our work. We depend ' .
+            'on donations to build new features, fix bugs, and keep AzuraCast modern, accessible and free.',
+        );
+        $notification->type = FlashLevels::Info->value;
+
+        $notification->actionLabel = __('Donate to AzuraCast');
+        $notification->actionUrl = 'https://donate.azuracast.com/';
+
+        $event->addNotification($notification);
+    }
+}