Replace "coin" with "network"

The Processor's coins folder referred to the networks it could process, as did
its Coin trait. This, and other similar cases throughout the codebase, have now
been corrected.

Also corrects dated documentation for a key pair is confirmed under the
validator-sets pallet.

processor/messages/src/lib.rs

@@ -14,7 +14,7 @@ use validator_sets_primitives::{ValidatorSet, KeyPair};
 #[derive(Clone, Copy, PartialEq, Eq, Debug, Zeroize, Serialize, Deserialize)]
 pub struct SubstrateContext {
   pub serai_time: u64,
-  pub coin_latest_finalized_block: BlockHash,
+  pub network_latest_finalized_block: BlockHash,
 }
 
 pub mod key_gen {
@@ -50,7 +50,7 @@ pub mod key_gen {
     // Created shares for the specified key generation protocol.
     Shares { id: KeyGenId, shares: HashMap<Participant, Vec<u8>> },
     // Resulting keys from the specified key generation protocol.
-    GeneratedKeyPair { id: KeyGenId, substrate_key: [u8; 32], coin_key: Vec<u8> },
+    GeneratedKeyPair { id: KeyGenId, substrate_key: [u8; 32], network_key: Vec<u8> },
   }
 }
 
@@ -165,7 +165,7 @@ pub mod substrate {
         CoordinatorMessage::ConfirmKeyPair { context, .. } => context,
         CoordinatorMessage::SubstrateBlock { context, .. } => context,
       };
-      Some(context.coin_latest_finalized_block)
+      Some(context.network_latest_finalized_block)
     }
   }
 
@@ -263,7 +263,7 @@ impl CoordinatorMessage {
       }
       CoordinatorMessage::Sign(msg) => {
         let (sub, id) = match msg {
-          // Unique since SignId includes a hash of the coin, and specific transaction info
+          // Unique since SignId includes a hash of the network, and specific transaction info
           sign::CoordinatorMessage::Preprocesses { id, .. } => (0, bincode::serialize(id).unwrap()),
           sign::CoordinatorMessage::Shares { id, .. } => (1, bincode::serialize(id).unwrap()),
           sign::CoordinatorMessage::Reattempt { id } => (2, bincode::serialize(id).unwrap()),