fix(instances): propagate IPAM errors during node initialization

Prevent nodes from being initialized without InternalIPs when IPAM
queries fail transiently. By returning errors instead of only logging
warnings, the node keeps its uninitialized taint and Kubernetes retries
until IPAM is available.

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

Author: nfm-corti

scaleway/instances.go

@@ -181,7 +181,8 @@ func (i *instances) instanceAddresses(server *scwinstance.Server) ([]v1.NodeAddr
 	// Try to get private network IPs
 	privateAddresses, err := i.getPrivateNetworkAddresses(server)
 	if err != nil {
-		klog.Warningf("error getting private network addresses for node %s: %v", server.Name, err)
+		klog.Warningf("failed to get private network addresses for node %s: %v", server.Name, err)
+		return nil, fmt.Errorf("failed to get private network addresses for node %s: %w", server.Name, err)
 	}
 
 	if len(privateAddresses) > 0 {
@@ -235,8 +236,8 @@ func (i *instances) getPrivateNetworkAddresses(server *scwinstance.Server) ([]v1
 	for _, pNIC := range server.PrivateNics {
 		nicAddresses, err := i.getIPsForPrivateNIC(server, pNIC, region)
 		if err != nil {
-			klog.Warningf("error getting IPs for private NIC %s on node %s: %v", pNIC.ID, server.Name, err)
-			continue
+			klog.Warningf("failed to query IPAM for node %s: %v", server.Name, err)
+			return addresses, fmt.Errorf("failed to query IPAM for node %s: %w", server.Name, err)
 		}
 		addresses = append(addresses, nicAddresses...)
 	}