xfail half of Phase 3.1: static calls on `#objc_class` aliases lower
to `objc_msg_send` against the class object (loaded once per module
via `objc_getClass`).
Test mirrors the Phase 3.0 pattern (`ffi-objc-dsl-01..04`): synthesize
a class at runtime via `objc_allocateClassPair`, add class methods on
the metaclass via `object_getClass(cls) + class_addMethod`, declare
the sx-side `#objc_class` with `static answer :: ...` / `static add ::
...`, then invoke `SxProbeStatic.answer()` / `.add(7, 35)`. Skips on
non-macOS.
Surface choice: the call site is `.` (`Cls.method(args)`), matching
JNI's existing static dispatch convention (`SurfaceView.new(ctx)`)
rather than the plan's notional `::` form. The lowering disambiguates
static vs instance by inspecting `method.is_static` on the foreign-
class member, same as JNI. Picking `.` avoids extending the parser
for a new postfix operator with no other use case.
Pre-3.1 snapshot pins the current bail diagnostic at
`lowerForeignStaticCall` (lower.zig:4475) — "static calls on
'objc_class' runtime not yet supported (Phase 3/4)" — fires twice
because both the niladic and the keyword-arg static call hit it.
exit=1.
164/164 tests; next commit implements the dispatch and flips the
snapshot to working output.