Driver/Rust: Implement suggestions by CodeRabbit

Author: amotl

docs/connect/rust.md

@@ -11,19 +11,29 @@ Connect to CrateDB from Rust applications.
 
 [postgres] is a synchronous Rust client for the PostgreSQL database.
 
-:::{rubric} Synopsis
+:::{rubric} Install
 :::
+```shell
+cargo add postgres
+```
 
+:::{rubric} Synopsis
+:::
 ```rust
 use postgres::{Client, NoTls};
 
-let mut client = Client::connect("host=localhost user=crate", NoTls)?;
-
-for row in client.query("SELECT mountain, height FROM sys.summits ORDER BY height DESC LIMIT 3", &[])? {
-    let mountain: &str = row.get(0);
-    let height: i32 = row.get(1);
-
-    println!("found mountain: {} {}", mountain, height);
+fn main() -> Result<(), Box<dyn std::error::Error>> {
+    let mut client = Client::connect("host=localhost user=crate", NoTls)?;
+
+    for row in client.query(
+        "SELECT mountain, height FROM sys.summits ORDER BY height DESC LIMIT 3",
+        &[],
+    )? {
+        let mountain: &str = row.get(0);
+        let height: i32 = row.get(1);
+        println!("found mountain: {} {}", mountain, height);
+    }
+    Ok(())
 }
 ```