Added a simple ros2 rust logger example

examples/minimal_logging/Cargo.toml

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+[package]
+name = "minimal_logging"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+rclrs = "*"
+std_msgs = "*"

examples/minimal_logging/README.md

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+# Differences between the [ROS2](https://docs.ros.org/en/jazzy/index.html) logger and standard [`println!()`](https://doc.rust-lang.org/std/macro.println.html)
+
+The [ROS2 logger](https://docs.ros.org/en/jazzy/Tutorials/Demos/Logging-and-logger-configuration.html) and
+[classic stdout (e.g., `println!`)](https://en.wikipedia.org/wiki/Standard_streams) differ in several key ways:
+
+1. **Severity Levels**:  
+   ROS2 provides structured log levels (`DEBUG`, `INFO`, `WARN`, `ERROR`, `FATAL`), enabling filtering based on urgency. `println!` outputs raw text without categorization.
+
+2. **Dynamic Control**:  
+   ROS2 allows runtime adjustment of logging levels (e.g., enabling `DEBUG` on-the-fly). `println!` statements cannot be disabled without code changes.
+
+3. **Metadata**:  
+   ROS2 automatically appends context (timestamp, node name, file/line number) to logs. `println!` requires manual addition of such details.
+
+4. **Integration**:  
+   ROS2 logs are captured by tools like `rqt_console` and can be routed to files/network. `println!` outputs only to stdout unless manually redirected.
+
+5. **Performance**:  
+   ROS2 optimizes by skipping disabled log levels (e.g., `DEBUG` if not active). `println!` always executes, incurring overhead regardless of need.
+
+6. **Configuration**:  
+   ROS2 logging is configurable via launch files/parameters (e.g., per-node log levels). `println!` offers no built-in configuration.
+
+**Example**:
+
+```rust
+// ROS2 logger (Rust example with rclrs)
+log!(node.info(), "Sensor value: {}", sensor_data);  // Adds metadata, severity, and runtime control
+
+// Classic stdout
+println!("Sensor value: {}", sensor_data);  // Simple, unstructured output
+```
+
+**Use ROS2 logger** for structured, controllable logging within the ROS2 ecosystem; use `println!` for quick, simple text output.

examples/minimal_logging/package.xml

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+
+<?xml version="1.0"?>
+<?xml-model
+   href="http://download.ros.org/schema/package_format3.xsd"
+   schematypens="http://www.w3.org/2001/XMLSchema"?>
+<package format="3">
+  <name>examples_rclrs_minimal_logging</name>
+  <version>0.1.0</version>
+  <description>Package containing an example of the logging mechanism in rclrs.</description>
+  <license>Apache License 2.0</license>
+
+  <depend>rclrs</depend>
+  <depend>rosidl_runtime_rs</depend>
+  <depend>std_msgs</depend>
+
+  <export>
+    <build_type>ament_cargo</build_type>
+  </export>
+</package>

examples/minimal_logging/src/main.rs

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+use rclrs::{create_node, log, Context, RclrsError, ToLogParams, QOS_PROFILE_DEFAULT};
+use std::{env, time::Duration};
+use std_msgs::msg::String as StringMsg;
+fn main() -> Result<(), RclrsError> {
+    let context = Context::new(env::args())?;
+
+    let node = create_node(&context, "minimal_logger")?;
+
+    let publisher = node.create_publisher("topic", QOS_PROFILE_DEFAULT)?;
+
+    let mut message = StringMsg::default();
+
+    let mut publish_count: u32 = 1;
+
+    while context.ok() {
+        message.data = format!("Hello, world! {}", publish_count);
+        log!(node.info(), "Publishing: [{}]", message.data);
+        publisher.publish(&message)?;
+        publish_count += 1;
+        std::thread::sleep(std::time::Duration::from_millis(500));
+    }
+    Ok(())
+}