Print command errors instead of unwrapping

ramen_egui/src/lib.rs

@@ -101,7 +101,12 @@ impl NodeEditor {
             };
 
             if let Some(cmd) = cmd {
-                self.cmd_history.push(&mut self.graph, cmd).unwrap();
+                let cmd_debug = format!("{:#?}", cmd);
+
+                match self.cmd_history.push(&mut self.graph, cmd) {
+                    Ok(_) => {},
+                    Err(e) => eprintln!("{}:\n  {:#?}", cmd_debug, e),
+                }
             }
 
             self.pointer_state.action = PointerAction::Idle(None); // TODO idle pointer targeting