Move autopilots into autopilot_state

[peterjan]

This migrates the autopilots to a single autopilot_state table, effectively removing the concept of multiple autopilots. I think autopilot state can be defined as config + the current period, I opted to keep the AutopilotConfig which can be updated in the bus. The current_period can be updated separately, which solves a race in the autopilot but that won't be an issue anyway since we're merging autopilot and bus. Tested on SQLite, not (yet) on MySQL, want to get a round of reviews in first.

[n8maninger]

Similar conversation: since we now have initial contract funding instead of a global allowance and refreshing a contract in v2 will be less painful, are these even necessary? Attempting to calculate this ahead of time adds unnecessary setup complexity and overhead. It may end up in more contracts overall, but storage utilization could be more efficient if the scoring didn't need to check for storage space available based on expected storage * redundancy / target contracts.

If a host runs out of storage space, but is otherwise in working condition, form a contract with a new host instead of churning it out of the set.

[ChrisSchinnerl]

We could get rid of the remaining storage score and simplify the collateral score and instead just check whether a host is already full / out of collateral before forming a contract without giving them a score.

[peterjan]

Thanks @n8maninger for the review. I combined your suggestion into a separate issue and plan to F/U with that immediately after this one. Getting rid of the current period never crossed my mind, but since we got rid of allowance that's now a very logical next step indeed. I won't resolve the open comments to allow further discussion.

[ChrisSchinnerl]

This looks pretty good overall. Just need to make sure

1. migrations were manually tested
2. we make sure the changes here are consistent with refactor(renterd): remove contract sets web#810 and that we somewhat merge these together

[peterjan]

This looks pretty good overall. Just need to make sure

1. migrations were manually tested
   DONE
2. we make sure the changes here are consistent with refactor(renterd): remove contract sets web#810 and that we somewhat merge these together
   Either we have to extend this PR with every F/U PR to dedupe autopilots and contract sets, that's going to be roughly 4k loc change though. Another option is to split the UI PR.

[ChrisSchinnerl]

Lgtm. @alexfreska any chance we can break out the changes of your big UI PR relevant to this PR and then tag a version? That way we could update the UI in this PR to make sure we don't break the UI when merging this.