refactor(identity): follow naming conventions for conversion methods

This PR renames some method names that don't follow Rust naming conventions or behave differently from what the name suggests:
- Enforce "try" prefix on all methods that return `Result`.
- Enforce "encode" method name for methods that return encoded bytes.
- Enforce "to_bytes" method name for methods that return raw bytes.
- Enforce "decode" method name for methods that convert encoded key.
- Enforce "from_bytes" method name for methods that convert raw bytes.

Pull-Request: #3775.

protocols/identify/src/protocol.rs

@@ -169,7 +169,7 @@ where
         .map(|addr| addr.to_vec())
         .collect();
 
-    let pubkey_bytes = info.public_key.to_protobuf_encoding();
+    let pubkey_bytes = info.public_key.encode_protobuf();
 
     let message = proto::Identify {
         agentVersion: Some(info.agent_version),
@@ -235,7 +235,7 @@ impl TryFrom<proto::Identify> for Info {
             addrs
         };
 
-        let public_key = PublicKey::from_protobuf_encoding(&msg.publicKey.unwrap_or_default())?;
+        let public_key = PublicKey::try_decode_protobuf(&msg.publicKey.unwrap_or_default())?;
 
         let observed_addr = match parse_multiaddr(msg.observedAddr.unwrap_or_default()) {
             Ok(a) => a,
@@ -386,7 +386,7 @@ mod tests {
             publicKey: Some(
                 identity::Keypair::generate_ed25519()
                     .public()
-                    .to_protobuf_encoding(),
+                    .encode_protobuf(),
             ),
         };