Support forced note-discovery resync

[nventuro]

Once #9365 goes in, it should be fairly easy to wipe the indices for any given contract, causing for them to process all tags when they next do note discovery. This could help with scenarios in which the sender has accidentally re-used old indices, e.g. due to sending from multiple out-of-sync devices.

Any notes that were previously known and have been found again would simply be skipped.

[nventuro]

See this comment from #9572

I'm thinking it might make sense to refactor the taggingSecretIndexes db to be easier to use (instead of indexing by the index, maybe exposing an API like getReceptionTaggingSecret(sender) and getTransmissionTaggingSecret(recipient). That way we can clean up the indexes when we remove someone from the addressbook?