108/108 regression tests pass (+ffi-objc-call-09-in-construct,
+issue-0038 from the prior commit).
One trivial Obj-C call (`[obj hash]` returning NSUInteger) routed
through four sx surface constructs:
1. struct method body Probe.fetch
2. protocol impl method body impl Hashable for Probe
3. closure value body make_hasher
4. generic function body hash_through(recv: $T)
No new ABI shapes touched — pins that the `objc_msg_send` lowering
emits identical call shapes regardless of enclosing scope. Each
case validates the result `h_N == h_1` after threading `recv`
appropriately for each context.
The closure path reaches `recv` via a module-level global rather
than capturing the surrounding parameter — issue-0038 (prior
commit) documents the closure free-variable analyzer missing the
`FfiIntrinsicCall` node, with a clean workaround pinned.
