Deserialization and error handling improvements

examples/conversation.rs

@@ -14,6 +14,8 @@ async fn main() -> Result<(), Box<dyn std::error::Error>> {
     let project_id = std::env::var("PROJECT_ID")?;
     let location_id = std::env::var("LOCATION_ID")?;
 
+    tracing_subscriber::fmt().init();
+
     let vertex_client = VertexClient::new(
         authentication_manager,
         api_endpoint,
@@ -21,6 +23,8 @@ async fn main() -> Result<(), Box<dyn std::error::Error>> {
         location_id,
     );
 
+    tracing::info!("Starting conversation...");
+
     let mut conversation = Conversation::new();
     loop {
         let message: String = Input::with_theme(&ColorfulTheme::default())