add tracing

src/main.rs

@@ -1,6 +1,18 @@
 use anyhow::Result;
+use tracing::info;
+use tracing_subscriber::{layer::SubscriberExt, util::SubscriberInitExt, EnvFilter, Registry};
 
 fn main() -> Result<()> {
+    let registry = Registry::default().with(EnvFilter::from_default_env());
+
+    info!("Starting cargo-minimize");
+
+    let tree_layer = tracing_tree::HierarchicalLayer::new(2)
+        .with_targets(true)
+        .with_bracketed_fields(true);
+
+    registry.with(tree_layer).init();
+
     cargo_minimize::minimize()?;
 
     Ok(())