fix(admin): carry filer addresses as ServerAddress in plugin cluster context (#9600)

The plugin cluster context forwarded filers as gRPC-only addresses
(host:grpcPort). The admin-script worker stored that in
ShellOptions.FilerAddress, whose shell commands re-derive the gRPC port
via ToGrpcAddress() and re-add the +10000 offset, dialing a non-existent
host:28888.

Carry filers in pb.ServerAddress form (host:httpPort.grpcPort) and let
each consumer convert when it dials: the admin shell uses it verbatim,
while the s3_lifecycle and iceberg workers collapse it to a gRPC address.
Rename the proto field filer_grpc_addresses -> filer_addresses so the
name matches the content.

weed/admin/plugin/cluster_rate_limit.go

@@ -113,7 +113,7 @@ func cloneClusterContext(in *plugin_pb.ClusterContext) *plugin_pb.ClusterContext
 	}
 	out := &plugin_pb.ClusterContext{
 		MasterGrpcAddresses: in.MasterGrpcAddresses,
-		FilerGrpcAddresses:  in.FilerGrpcAddresses,
+		FilerAddresses:      in.FilerAddresses,
 		VolumeGrpcAddresses: in.VolumeGrpcAddresses,
 		S3GrpcAddresses:     in.S3GrpcAddresses,
 	}