062 reject empty brace payload

// Test: Parser should reject empty braces {} in branch payloads
// Empty braces are meaningless - use void events (no branches) or identity syntax instead

const std = @import("std");

// WRONG: Empty braces in branch payload
// Should be either:
// - A void event: ~event done {} (no branches at all)
// - Identity syntax: | done SomeType
~event verify {}
| done