fix(events): point Messaging settings at suite defaults, not API keys

Mirror Care: suite platform keys count as ready for attendee email/SMS;
Account Messaging is primary, product Bird/SMS keys are advanced.
SmsService now prefers channel=suite before customer API keys.

tests/Feature/EventsMessagingIntegrationsTest.php

@@ -39,7 +39,8 @@ class EventsMessagingIntegrationsTest extends TestCase
             ->assertOk()
             ->assertSee('SMS')
             ->assertSee('Email')
-            ->assertSee('credentials for outbound messaging');
+            ->assertSee('work by default')
+            ->assertSee('optional');
     }
 
     public function test_saving_sms_credentials_encrypts_key(): void