feat: add custom response documentation

Author: mychidarko

src/docs/http/response.md

@@ -61,11 +61,11 @@ Plain text responses can be created using the `plain()` method. This method acce
 
 ::: code-group
 
-```php [Functional Mode]
+```php:no-line-numbers [Functional Mode]
 response()->plain('Hello, world!');
 ```
 
-```php [Leaf Instance]
+```php:no-line-numbers [Leaf Instance]
 $app->response()->plain('Hello, world!');
 ```
 
@@ -258,6 +258,38 @@ $app->response()->xml('<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema"
 
 :::
 
+### Custom responses
+
+If you need to create a custom response, which is not covered by the methods above, you can use the `custom()` method. This method accepts 2 parameters:
+
+- the content to output
+- an optional status code (defaults to 200/OK)
+
+::: code-group
+
+```php:no-line-numbers [Functional Mode]
+response()
+  ->withHeader([
+    'Content-Type' => 'application/pdf',
+    'Content-Length' => $dataLength,
+    'Content-Disposition' => "inline; filename=\"$filename\""
+  ])
+  ->custom($rawData);
+```
+
+```php:no-line-numbers [Leaf Instance]
+$app
+  ->response()
+  ->withHeader([
+    'Content-Type' => 'application/pdf',
+    'Content-Length' => $dataLength,
+    'Content-Disposition' => "inline; filename=\"$filename\""
+  ])
+  ->custom($rawData);
+```
+
+:::
+
 ## Headers
 
 Headers are a way for your server to send additional information along with your request. This information can be anything from the type of content you're sending back, to the status code of your response, to the type of server you're using.