Resolve #360 (#456)

* Remove NetworkId from processor-messages

Because intent binds to the sender/receiver, it's not needed for intent.

The processor knows what the network is.

The coordinator knows which to use because it's sending this message to the
processor for that network.

Also removes the unused zeroize.

* ProcessorMessage::Completed use Session instead of key

* Move SubstrateSignId to Session

* Finish replacing key with session

processor/src/tests/key_gen.rs

@@ -10,10 +10,7 @@ use frost::{Participant, ThresholdParams, tests::clone_without};
 use serai_db::{DbTxn, Db, MemDb};
 
 use sp_application_crypto::sr25519;
-use serai_client::{
-  primitives::NetworkId,
-  validator_sets::primitives::{Session, ValidatorSet, KeyPair},
-};
+use serai_client::validator_sets::primitives::{Session, KeyPair};
 
 use messages::key_gen::*;
 use crate::{
@@ -21,8 +18,7 @@ use crate::{
   key_gen::{KeyConfirmed, KeyGen},
 };
 
-const ID: KeyGenId =
-  KeyGenId { set: ValidatorSet { session: Session(1), network: NetworkId::Monero }, attempt: 3 };
+const ID: KeyGenId = KeyGenId { session: Session(1), attempt: 3 };
 
 pub async fn test_key_gen<N: Network>() {
   let mut entropies = HashMap::new();
@@ -139,7 +135,11 @@ pub async fn test_key_gen<N: Network>() {
     let key_gen = key_gens.get_mut(&i).unwrap();
     let mut txn = dbs.get_mut(&i).unwrap().txn();
     let KeyConfirmed { mut substrate_keys, mut network_keys } = key_gen
-      .confirm(&mut txn, ID.set, KeyPair(sr25519::Public(res.0), res.1.clone().try_into().unwrap()))
+      .confirm(
+        &mut txn,
+        ID.session,
+        KeyPair(sr25519::Public(res.0), res.1.clone().try_into().unwrap()),
+      )
       .await;
     txn.commit();