filer: preserve existing TTL during CreateEntry/UpdateEntry gRPC calls

This ensures that metadata load correctly restores entries with their
original TTL instead of overwriting with the default from filer.conf.
Fixes #8159.

weed/server/filer_grpc_server.go

@@ -155,7 +155,9 @@ func (fs *FilerServer) CreateEntry(ctx context.Context, req *filer_pb.CreateEntr
 	newEntry.Chunks = chunks
 	// Don't apply TTL to remote entries - they're managed by remote storage
 	if newEntry.Remote == nil {
-		newEntry.TtlSec = so.TtlSeconds
+		if newEntry.TtlSec == 0 {
+			newEntry.TtlSec = so.TtlSeconds
+		}
 	} else {
 		newEntry.TtlSec = 0
 	}