* consensus: fix batch handling when we don't have a full list of outputs.
* change `scan_chain` to new API
* clippy
* add a test for calculating multiple difficulties
* fmt
* rx_seed -> rx_vms
* consensus-rules: ring members younger than current block.
* only create rx vms when required.
* fix rx initiation when syncing
* add single block verification (no batch)
* update serai
Before we were using tokio's `spawn_blocking`, which wasn't ideal as this put tasks in a queue to be put on rayon's pool.
Instead, now we create an oneshot and use rayon::spawn.
This means we don't have to rely on people giving the verifier the correct txs for a block.
Also allows some speedup as we can put the fetching of outputs on a different task.
