142 nominal in pipeline

// TEST: Using nominal types in event pipelines
//
// Define nominal types ~string and ~int, then use them
// as event parameters in a pipeline.
//
// Expected: Compiles and runs with nominal types in events

~import "$std/types"
~import "$std/io"
~import "$std/control"

const std = @import("std");

// Define nominal types
~string(Username)
~int(UserId)

// Event that takes nominal types
~event greet_user { name: Username, id: UserId }
| greeted {}

~proc greet_user {
    std.debug.print("Hello {s} (ID: {d})\n", .{ name, id });
    return .{ .greeted = .{} };
}

// Use in a pipeline
~const({ user: "alice", uid: @as(i64, 42) })
| as data |> greet_user(name: data.user, id: data.uid)
    | greeted |> _