Add redirect response builder to controller.

src/Router/Controller.php

@@ -57,6 +57,22 @@ abstract class Controller
 		);
 	}
 
+	/**
+	 * Build a redirect response.
+	 * @param string $to Location to redirect to.
+	 * @param StatusCode $statusCode The status code to send back. 301 Moved Permanently by default.
+	 * @return ResponseInterface Built response.
+	 */
+	public function redirect(string $to, StatusCode $statusCode = StatusCode::MovedPermanently): ResponseInterface
+	{
+		return new Response(
+			// Pass the status code.
+			status: $statusCode->value,
+			// Pass redirect location.
+			headers: ["Location" => $to],
+		);
+	}
+
 	/**
 	 * Build a text response.
 	 * @param string $value The text value to pass.