Contains minor changes to async usage in line with upstream API changes.
I believe a feedback issue we were seeing with offset changes (the only
component using async write flow) may have been resolved by these
upstream changes (see [release
notes](https://github.com/realm/realm-dotnet/releases/tag/10.14.0)) but
am not investigating further just yet.
One of my pending work items for post-realm merge.
The lowest-level import task is no longer asynchronous, as we don't want
it to span multiple threads to allow easier interaction with realm.
Removing the `Task` spec simplifies a heap of usages.
Individual usages should decide whether they want to run the import
asynchronously, by either using an alternative override or spooling up a
thread themselves.
This is one step closer to sanity in terms of physical files. As per the
comment I have left in place, we really should be checking file sizes or
hashes, but to keep things simple and fast I've opted to just cover the
"missing file" scenario for now.
Ran into this when testing against a foreign `client.realm` by:
- Noticing a beatmap doesn't load
- Deleting said beatmap
- Downloading via beatmap overlay
- Beatmap is restored but still doesn't work
Note that I've kept the logic where this will undelete an existing
import rather than create one from fresh, as I think that is beneficial
to the user (ie. it will still keep any linked scores on restore).