Hampered authority fallback

[8e8b2c]

I've encountered an awkward bug with the faceit api - a match result's gone missing. If we're lucky this won't happen during our test run, but it's opened my eyes to a new of problems we'll want to solve: i.e. when the authority's hampered, what can be done to unstick the system.

One choice would be to ignore the missing result - but that could be rather outrageous if it significantly impacts the leaderboard.

If the information is available elsewhere (if even partially), then it might be worth allowing some method for entering the data manually. (Either via the authority, or some community intervention)

If we do "censor" a missing result, then the error should probably be published instead to at least account for it.

[8e8b2c]

Possible Approaches

Approach 1:

Some process where in the relevant authority is still the publisher, and implements their own governance (potentially democratic) for receiving missing data from the community.

Approach 2:

Similar to the above, but with a named fallback authority in the signing offer's trust tree. I.e. that fallback authority specialises in crowd sourcing.

Approach 3:

Crowd sourcing rules are encoded into the happ DNA. (Likely very complicated to spec and get right!)

[8e8b2c]

Setting priority to low since Approaches 1 & 2 are already possible without happ changes. (Though work would still need to be done by projects maintaining publishers.)