Fix remote.meta.sync TTL issue (#8021) (#8030)

* Fix remote.meta.sync TTL issue (#8021)

Remote entries should not have TTL applied because they represent files
in remote storage, not local SeaweedFS files. When TTL was configured on
a prefix, remote.meta.sync would create entries that immediately expired,
causing them to be deleted and recreated on each sync.

Changes:
- Set TtlSec=0 explicitly when creating remote entries in remote.meta.sync
- Skip TTL application in CreateEntry handler for entries with Remote field set

Fixes #8021

* Add TTL protection for remote entries in update path

- Set TtlSec=0 in doSaveRemoteEntry before calling UpdateEntry
- Add server-side TTL protection in UpdateEntry handler for remote entries
- Ensures remote entries don't inherit or preserve TTL when updated

weed/server/filer_grpc_server.go

@@ -153,7 +153,12 @@ func (fs *FilerServer) CreateEntry(ctx context.Context, req *filer_pb.CreateEntr
 	}
 	newEntry := filer.FromPbEntry(req.Directory, req.Entry)
 	newEntry.Chunks = chunks
-	newEntry.TtlSec = so.TtlSeconds
+	// Don't apply TTL to remote entries - they're managed by remote storage
+	if newEntry.Remote == nil {
+		newEntry.TtlSec = so.TtlSeconds
+	} else {
+		newEntry.TtlSec = 0
+	}
 
 	createErr := fs.filer.CreateEntry(ctx, newEntry, req.OExcl, req.IsFromOtherCluster, req.Signatures, req.SkipCheckParentDirectory, so.MaxFileNameLength)
 
@@ -185,6 +190,11 @@ func (fs *FilerServer) UpdateEntry(ctx context.Context, req *filer_pb.UpdateEntr
 	newEntry := filer.FromPbEntry(req.Directory, req.Entry)
 	newEntry.Chunks = chunks
 
+	// Don't apply TTL to remote entries - they're managed by remote storage
+	if newEntry.Remote != nil {
+		newEntry.TtlSec = 0
+	}
+
 	if filer.EqualEntry(entry, newEntry) {
 		return &filer_pb.UpdateEntryResponse{}, err
 	}