Add cancel snooze

- Add common request validation function

src/public/components/request/add-note.php

@@ -3,12 +3,8 @@
 use MyPrayerJournal\{Auth, Layout, Request};
 
 require '../../../start.php';
-if ($_SERVER['REQUEST_METHOD'] <> 'GET') not_found();
 
-Auth::requireUser(false);
-
-$req = Request::byId($_GET['id']);
-if (!$req) not_found();
+$req = validate_request($_GET['id'], ['GET'], false);
 
 Layout::bareHead(); ?>
 <form hx-post="/request/note?id=<?=$req->id?>">