fix: isolate public subscribe from integration job failures

Queue Weeztix/Mailwizz after the HTTP response and catch dispatch errors.
Jobs log Mailwizz/Weeztix API failures without rethrowing so sync driver
and terminating callbacks do not surface 500s after a successful create.

Add JS fallback for non-JSON error responses, deployment note, and a
regression test for failing Mailwizz under QUEUE_CONNECTION=sync.

Made-with: Cursor

app/Jobs/SyncSubscriberToMailwizz.php

@@ -47,6 +47,18 @@ class SyncSubscriberToMailwizz implements ShouldBeUnique, ShouldQueueAfterCommit
     }
 
     public function handle(): void
+    {
+        try {
+            $this->runSync();
+        } catch (Throwable $e) {
+            Log::error('SyncSubscriberToMailwizz: integration failed; subscriber remains local (use admin resync if needed)', [
+                'subscriber_id' => $this->subscriber->id,
+                'message' => $e->getMessage(),
+            ]);
+        }
+    }
+
+    private function runSync(): void
     {
         $subscriber = Subscriber::query()
             ->with(['preregistrationPage.mailwizzConfig'])