WinningPoSt submit

[snadrus]

User Story

The user wants WinningPoSt on the chain.

Acceptance Criteria

It arrives on-chain even under any arrangement of difficult circumstances as long as some lotus-provider is running.

Deliverables

Preview Give feedback

1. Add to the HA post-to-chain code can get a TryThisEpoch() to attempt to run any for this epoch that may be late-added.
2. Call this at the end of WinningPoSt work to write this to the chain if we are late-ran.
3. Call TryThisEpoch() at start-up so there is no possible way a running stance can miss a deadline.

Technical Breakdown

Tasks

Preview Give feedback

1. Reuse wdpost_proofs code as much as possible.
2. Ensure that multiple attempts to write the same message to the table will result in conflicts instead of 2 chain entries.
3. Handle post errors with other systems doing retries (task engine).

Testing

Preview Give feedback

1. Ensure WinningPoSt makes it to chain even under difficult circumstances. Ex: the lotus-provider that gets the work loses the daemon but retains database reachability.

[rjan90]

Closing since WinningPoSt has been implemented in Lotus-Provider with #11410