052 pattern branches

// ============================================================================
// TEST: Pattern Branches Parser Support
// ============================================================================
// Verifies that the parser correctly handles [...] pattern branch syntax.
// Pattern branches allow opaque expressions as branch names for DSL transforms.
//
// The [...] content is passed through as the branch name - transforms interpret it.
// ============================================================================

// Simple event to test pattern branches
~event test_patterns {}
| ok {}

~proc test_patterns {
    return .{ .ok = .{} };
}

// Test that pattern branches parse correctly
// The branch names are [GET /users/:id] etc - opaque to the compiler
~test_patterns()
| [GET /users/:id] |> ok {}
| [POST /users] |> ok {}
| [nested [brackets] work] |> ok {}
| [* -> stopped] |> ok {}  // State machine style
| ok |> _  // Normal branch still works

// Verify nested patterns work
~test_patterns()
| [/admin/*] |>
    test_patterns()
    | [GET /dashboard] |> ok {}
    | ok |> _
| ok |> _