fix: correct supavisor service name in docker-compose override

The service is named 'supavisor' in the base compose file,
not 'supabase-pooler'.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

infrastructure/docker-compose.override.yml

@@ -28,7 +28,7 @@ services:
       - proxy
 
   # Pooler: fixer Hostname damit Erlang-VM den eigenen Namen auflösen kann
-  supabase-pooler:
+  supavisor:
     hostname: supabase-pooler
 
   # Nightly Scheduler: APNs-Ping + Resonance-Milestones