style: auto-format example files with lux fmt

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

examples/test_math.lux

@@ -1,6 +1,3 @@
-// Math Test Suite
-// Run with: lux test examples/test_math.lux
-
 fn test_addition(): Unit with {Test} = {
     Test.assertEqual(4, 2 + 2)
     Test.assertEqual(0, 0 + 0)