feat(jobs): implement encrypted queue jobs

- Add ShouldBeEncrypted interface to all queue jobs to encrypt sensitive
  job payloads
- Configure explicit retry policies for messaging jobs (5 attempts,
  10-second backoff)

app/Jobs/SendMessageToTelegramJob.php

@@ -22,6 +22,11 @@ class SendMessageToTelegramJob implements ShouldBeEncrypted, ShouldQueue
      */
     public $tries = 5;
 
+    /**
+     * The number of seconds to wait before retrying the job.
+     */
+    public $backoff = 10;
+
     /**
      * The maximum number of unhandled exceptions to allow before failing.
      */