Add an r2r_info example to dump the ROS environment report

r2r_common/examples/r2r_info.rs

@@ -0,0 +1,44 @@
+//! Prints the environmental information for r2r.
+
+use r2r_common::RosMsg;
+
+fn main() {
+    println!("# r2r Information");
+
+    println!("## Env Hash");
+    println!("{}", r2r_common::get_env_hash());
+    println!();
+
+    println!("## Messages");
+    println!();
+    for msg in r2r_common::get_wanted_messages() {
+        let RosMsg {
+            module,
+            prefix,
+            name,
+        } = msg;
+        println!("- `{module}/{prefix}/{name}`");
+    }
+    println!();
+
+    println!("## Cargo ROS Distro");
+    println!();
+    println!("```");
+    r2r_common::print_cargo_ros_distro();
+    println!("```");
+    println!();
+
+    println!("## Cargo Link Watches");
+    println!();
+    println!("```");
+    r2r_common::print_cargo_watches();
+    println!("```");
+    println!();
+
+    println!("## Cargo Link Search");
+    println!();
+    println!("```");
+    r2r_common::print_cargo_link_search();
+    println!("```");
+    println!();
+}