133 instantiation param mismatch

// RED PIN, MUST_FAIL (type-system design walk, 2026-07-06/07).
// REWRITTEN — the old "wrong arity in Pair<A>" intent belonged to the
// banned parametric grammar. The surviving intent is the deeper one:
// NOMINAL DISTINCTNESS. Two structurally identical declared types are
// DIFFERENT types; cross-use is rejected at the Koru layer citing both
// declarations. Today's scaffolding emits plain Zig aliases, so this
// leaks through silently — which is exactly the old cluster TODO's
// named gap ("without nominal distinctness"), now pinned as a
// rejection.

~import std/types

const std = @import("std");

~std/types:struct(Meters) {
    v: i64,
}

~std/types:struct(Feet) {
    v: i64,
}

~event get-altitude {}
| alt Feet

~proc get-altitude|zig {
    return .{ .alt = Feet{ .v = 30000 } };
}

~event show-meters { m: Meters }

~proc show-meters|zig {
    std.debug.print("{d}m\n", .{m.v});
}

// ERROR: Feet where Meters is expected — same shape, distinct types
~get-altitude()
| alt a |> show-meters(m: a)