master: keep disk_id when registering volumes from incremental heartbeats (#10686)

The volume server names the directory index in every
VolumeShortInformationMessage, but NewVolumeInfoFromShort dropped it, so
volumes registered through the incremental new-volume path showed
disk_id 0 at the master until a full report -- misreporting multi-dir
servers in volume.list and the per-physical-disk topology views.

Claude-Session: https://claude.ai/code/session_01QdTEEPbg4MtcoEGwqbgtZC

weed/storage/volume_info.go

@@ -67,6 +67,7 @@ func NewVolumeInfoFromShort(m *master_pb.VolumeShortInformationMessage) (vi Volu
 		Id:         needle.VolumeId(m.Id),
 		Collection: internVolumeString(m.Collection),
 		Version:    needle.Version(m.Version),
+		DiskId:     m.DiskId,
 	}
 	rp, e := super_block.NewReplicaPlacementFromByte(byte(m.ReplicaPlacement))
 	if e != nil {

weed/storage/volume_info_test.go

@@ -3,6 +3,7 @@ package storage
 import (
 	"testing"
 
+	"github.com/seaweedfs/seaweedfs/weed/pb/master_pb"
 	"github.com/seaweedfs/seaweedfs/weed/storage/needle"
 )
 
@@ -25,3 +26,17 @@ func TestSortVolumeInfos(t *testing.T) {
 		}
 	}
 }
+
+func TestNewVolumeInfoFromShortKeepsDiskId(t *testing.T) {
+	vi, err := NewVolumeInfoFromShort(&master_pb.VolumeShortInformationMessage{
+		Id:      7,
+		Version: 3,
+		DiskId:  3,
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if vi.DiskId != 3 {
+		t.Fatalf("DiskId = %d, want 3", vi.DiskId)
+	}
+}