style: auto-format example files with lux fmt

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

examples/standard/hello_world.lux

@@ -1,7 +1,3 @@
-// The classic first program
-// Expected output: Hello, World!
-
-fn main(): Unit with {Console} =
-    Console.print("Hello, World!")
+fn main(): Unit with {Console} = Console.print("Hello, World!")
 
 let output = run main() with {}