l10n: adjust the documentation

docs/src/l10n.md

@@ -66,30 +66,29 @@ You can override the locale at runtime by running:
 
 ## 📥 Retrieving Messages
 
-Two APIs are available:
+We have a single macro to handle translations.
+It can be used in two ways:
 
-### `get_message(id: &str) -> String`
+### `translate!(id: &str) -> String`
 
 Returns the message from the current locale bundle.
 
 ```
-    let msg = get_message("id-greeting");
+    let msg = translate!("id-greeting");
 ```
 
 If not found, falls back to `en-US`. If still missing, returns the ID itself.
 
 ---
 
-### `get_message_with_args(id: &str, args: HashMap<String, String>) -> String`
+### `translate!(id: &str, args: key-value pairs) -> String`
 
 Supports variable interpolation and pluralization.
 
 ```
-    let msg = get_message_with_args(
+    let msg = translate!(
         "error-io",
-        HashMap::from([
-            ("error".to_string(), std::io::Error::last_os_error().to_string())
-        ])
+        "error" => std::io::Error::last_os_error()
     );
 ```