Consider adding a feature to repair pinned collections that contain missing or damaged chunks

[notanatol]

Summary

After the release of the tool that detects missing/damaged chunks belonging to pinned content - the follow up feature would be adding the capability to re-insert the faulty chunks in place, from an existent file or by fetching the chunk from the network.

Motivation

For nodes with large number of pinned references it's bothersome to unpin/re-upload the entire collection, so a more fine grained solution is needed.