fix: add defensive nil check for placeholderHandler

Reorder condition checks to verify placeholder configuration before
checking handler to prevent potential panics if placeholder is enabled
in spec but handler is nil.

Signed-off-by: malpou <malthe@grundtvigsvej.dk>

Author: malpou

interceptor/proxy_handlers.go

@@ -77,7 +77,8 @@ func newForwardingHandler(
 		hasFailover := httpso.Spec.ColdStartTimeoutFailoverRef != nil
 
 		// Check if we should serve a placeholder page
-		if placeholderHandler != nil && httpso.Spec.PlaceholderConfig != nil && httpso.Spec.PlaceholderConfig.Enabled {
+		// Ensure placeholderHandler is not nil to prevent panics even if placeholder is enabled in spec
+		if httpso.Spec.PlaceholderConfig != nil && httpso.Spec.PlaceholderConfig.Enabled && placeholderHandler != nil {
 			endpoints, err := endpointsCache.Get(httpso.GetNamespace(), httpso.Spec.ScaleTargetRef.Service)
 			if err != nil {
 				// Error getting endpoints cache - return 503 Service Unavailable