Auto-recovery when segment is collapsed on server

[Jackie-Jiang]

Segment could collapse during the pre-process on server side, e.g. server shut down in the middle of the segment preprocessing. In such scenario, the next time when trying to load the segment, the server should drop the collapsed segment and download a new copy from the controller/deep storage.
We need to handle this logic in:

• Segment loading when server starts
• Refreshing segment
• Reloading segment