kvm2: apply the milestone review

Shorter start wait with immediate verdicts for dead or paused domains,
ListByTag without state or address RPCs, Timeout for an expired check
round, no adoption of unmarked domains, reference-counted keyed locks,
dead options removed, HEAD fallback on any non-2xx.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

internal/provider/kvm2/delete.go

@@ -26,7 +26,7 @@ func (p *Provider) Delete(ctx context.Context, providerID string) error {
 	log := p.logger(ctx).WithValues("host", hostName, "name", name)
 	host, err := p.host(hostName)
 	if err != nil {
-		log.Info("host is not configured; delete has nothing to clean up", "id", providerID)
+		log.V(1).Info("host is not configured; delete has nothing to clean up", "id", providerID)
 		return nil
 	}
 	unlock, err := p.lockName(ctx, name)
@@ -82,7 +82,7 @@ func removeDomain(ctx context.Context, log logr.Logger, be backend, name string)
 func removeVolumes(ctx context.Context, log logr.Logger, be backend, poolName, name string) error {
 	pool, err := be.StoragePoolLookupByName(ctx, poolName)
 	if hasCode(err, libvirt.ErrNoStoragePool) {
-		log.Info("pool not found, no volumes to delete", "pool", poolName)
+		log.V(1).Info("pool not found, no volumes to delete", "pool", poolName)
 		return nil
 	}
 	if err != nil {