feat(tvix/castore/refscan): share the scanner between readers r/8740

This changes the only actual state the ReferenceScanner has to use atomic bools, so it no longer requires a mutable borrow for .scan(). This allows passing an immutable borrow of a reference scanner to multiple threads which might be ingesting blobs in parallel, and using
them in the ReferenceReader or calling .scan() there.

Change-Id: Id5c30bcebb06bf15eae8c4451d70eb806cab722e
Reviewed-on: https://cl.tvl.fyi/c/depot/+/12528
Autosubmit: yuka <yuka@yuka.dev>
Reviewed-by: flokli <flokli@flokli.de>
Tested-by: BuildkiteCI

0 files changed, 0 insertions, 0 deletions