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/shell/command_remote_meta_sync.go

@@ -160,6 +160,7 @@ func pullMetadata(commandEnv *CommandEnv, writer io.Writer, localMountedDir util
 							FileSize: uint64(remoteEntry.RemoteSize),
 							Mtime:    remoteEntry.RemoteMtime,
 							FileMode: uint32(0644),
+							TtlSec:   0, // Remote entries should not have TTL
 						},
 						RemoteEntry: remoteEntry,
 					},