Get all processors to compile again

Requires splitting `serai-cosign` into `serai-cosign` and `serai-cosign-types`
so the processor don't require `serai-client/serai` (not correct yet).

coordinator/cosign/src/lib.rs

@@ -19,6 +19,8 @@ use serai_client::{
 use serai_db::*;
 use serai_task::*;
 
+use serai_cosign_types::*;
+
 /// The cosigns which are intended to be performed.
 mod intend;
 /// The evaluator of the cosigns.