108 effect handler autodischarge emits member

// PIN (auto-discharge ↔ effect-emitter boundary bug): when the auto-discharge
// inserter splices a disposal INTO an effect-branch (`!`) handler, the emitter
// mis-lowers the handler as a terminal switch arm instead of a `fn NAME`
// handler-struct member — yielding `Handlers_0 has no member named 'make'`.
//
// The handler `! make r |> use(r)` leaves `r`'s `active!` obligation live, so
// auto-discharge must insert `destroy(r)`. The INSERTED form breaks; the
// EXPLICIT form (`! make r |> use(r) |> destroy(r)`) compiles + runs fine —
// proving the bug is in the insertion→emission path, not multi-statement bodies
// and not auto-discharge detection (which fires correctly). Expected output is
// identical to the explicit-discharge version.
~import std/build
~std/build:requires { exe.linkLibC(); }
const std = @import("std");
const Resource = struct { id: usize };
const allocator = std.heap.c_allocator;

~event destroy { r: *Resource<!active> }
~proc destroy|zig { std.debug.print("freed {}\n", .{r.id}); allocator.destroy(r); }

~event use { r: *Resource<active> }
~proc use|zig { std.debug.print("using {}\n", .{r.id}); }

~pub event gen { n: usize }
! make *Resource<active!>
| done usize
~proc gen|zig {
    for (0..n) |i| {
        const r = allocator.create(Resource) catch unreachable;
        r.* = Resource{ .id = i };
        make(r);
    }
    return .{ .done = n };
}

~gen(n: 3)
! make r |> use(r)
| done _ |> _