feat: let admins notify all users about updated access codes

config/packages/messenger.yaml

@@ -21,7 +21,7 @@ framework:
             # Mail is deliberately NOT routed to async. Nothing starts a worker on the server --
             # deploy.php only stops them -- so a queued SendEmailMessage would be written to
             # messenger_messages and stay there, with no error anywhere and nobody notified.
-            # Sending happens in the request instead; BookingNotifier catches a transport
+            # Sending happens in the request instead; App\Email\Mailer catches a transport
             # failure so it can never fail the booking that triggered it. Route it back here
             # once a `messenger:consume async` worker actually runs.
             # Symfony\Component\Mailer\Messenger\SendEmailMessage: async

config/services.yaml

@@ -26,9 +26,8 @@ services:
         arguments:
             $logger: '@monolog.logger.audit'
 
-    # Booking notifications. The sender is also the To of every notification -- the actual
-    # recipients are Bcc'd -- so it has to be an address that may both send and receive.
-    App\Service\BookingNotifier:
+    # Every mail goes out from this address, one per recipient -- see App\Email\Mailer.
+    App\Email\Mailer:
         arguments:
             $sender: '%env(string:MAILER_FROM)%'