Add system phase 4 audits

- Add audit logging for system maintenance operations (cache/orphaned images/manual cleanup)
- Log account deletion request handling (requests/confirm/cancel)
- Log security actions (admin password resets, MFA enforcement changes, account lockouts)

supabase/functions/confirm-account-deletion/index.ts

@@ -89,6 +89,17 @@ export default createEdgeFunction(
       throw updateError;
     }
 
+    // Log to system activity log
+    await supabaseClient.rpc('log_system_activity', {
+      _user_id: context.userId,
+      _action: 'account_deletion_confirmed',
+      _details: {
+        request_id: deletionRequest.id,
+        scheduled_deletion_at: deletionRequest.scheduled_deletion_at,
+        account_deactivated: true,
+      }
+    });
+
     // Send confirmation email
     const forwardEmailKey = Deno.env.get('FORWARDEMAIL_API_KEY');
     const fromEmail = Deno.env.get('FROM_EMAIL_ADDRESS') || 'noreply@thrillwiki.com';