fix(ec): blanket-clean every destination over the full shard range (#9512)

* fix(ec): blanket-clean every destination over the full shard range

The previous cleanup pass walked t.sources only, with the shard ids the
topology had reported at detection time. In the wild, a destination can
end up with EC shards mounted that the topology snapshot didn't list —
shards on a sibling disk that hadn't heartbeated, or shards left over
from a concurrent attempt's mount step. FindEcVolume still returns
true, so the next ReceiveFile trips the mounted-volume guard.

Cleanup now unions t.sources (with ShardIds) and t.targets and issues
unmount + delete over [0..totalShards-1] on each. Both RPCs are
idempotent on missing shards, so the wider sweep is free.

Two new tests cover the gap: shards mounted beyond what t.sources
lists, and a target-only destination with no source row.

* log(ec): include disk_id in EC unmount/delete/refusal log lines

The current logs identify the volume and shard but leave disk_id off,
which makes the cross-server cleanup story hard to follow when
multiple disks of one server hold pieces of the same volume:

  UnmountEcShards 4121.1                              -> add disk_id
  ec volume video-recordings_4121 shard delete [1 5]  -> add per-loc disk_id
  volume server X:Y deletes ec shards from 4121 [...] -> add disk_id
  ReceiveFile: ec volume 4121 is mounted; refusing... -> add disk_ids

ReceiveFile's refusal now names the disk_ids actually holding the
mount so operators can see whether the next cleanup pass needs to
target a sibling disk. Added Store.FindEcVolumeDiskIds /
Store::find_ec_volume_disk_ids as the supporting primitive.

Mirrored in seaweed-volume/src/ (unmount log in Store::unmount_ec_shard,
heartbeat delete log in diff_ec_shard_delta_messages, refusal in the
ReceiveFile handler).

* test(ec): stub VolumeEcShardsUnmount/Delete on the fake volume server

The plugin-worker EC tests boot a fake volume server that embeds
UnimplementedVolumeServerServer. After the worker started calling
VolumeEcShardsUnmount + VolumeEcShardsDelete pre-distribute, the
default Unimplemented response surfaced as fourteen "method not
implemented" errors and TestErasureCodingExecutionEncodesShards
failed. Both RPCs are no-ops here — nothing on the fake server has
mounted state or persisted shard files to remove.

weed/server/volume_grpc_erasure_coding.go

@@ -327,9 +327,9 @@ func (vs *VolumeServer) VolumeEcShardsDelete(ctx context.Context, req *volume_se
 
 	glog.V(0).Infof("ec volume %s shard delete %v", bName, req.ShardIds)
 
-	for _, location := range vs.store.Locations {
+	for diskId, location := range vs.store.Locations {
 		if err := deleteEcShardIdsForEachLocation(bName, location, req.ShardIds); err != nil {
-			glog.Errorf("deleteEcShards from %s %s.%v: %v", location.Directory, bName, req.ShardIds, err)
+			glog.Errorf("deleteEcShards from disk_id:%d %s %s.%v: %v", diskId, location.Directory, bName, req.ShardIds, err)
 			return nil, err
 		}
 	}