Adds the constructor-invocation arm of the foreign-class DSL:
`SurfaceView.new(ctx)` (where `SurfaceView` is a `#foreign #jni_class`
with `static new :: (ctx: *Context) -> *Self;`) lowers to
`FindClass(env, "android/view/SurfaceView") + GetMethodID(env, cls,
"<init>", "(args)V") + NewObject(env, cls, mid, args...)`. Returns
the fresh jobject.
- inst.zig: `JniMsgSend.is_constructor` flag + `parent_class_path`
re-purposed to carry the class being constructed (alongside its
existing nonvirtual-super-class use). Mutually exclusive with
`is_static` / `is_nonvirtual`.
- lower.zig: `lowerCall.field_access` arm now recognises
`Alias.method(args)` where `Alias` resolves in `foreign_class_map`
and the matching member is `static`. `new` routes to a new
`lowerForeignStaticCall` that derives a `(args)V` JNI descriptor
and emits a `JniMsgSend` with `is_constructor=true`. Non-`new`
static calls report a clear "use #jni_static_call" diagnostic
until that sugar lands.
- emit_llvm.zig: new `NewObject` vtable slot (28) + `emitJniConstructor`
helper expanding the FindClass+GetMethodID+NewObject chain. The
jni_msg_send arm short-circuits to it when `is_constructor` is set.
Smoke `ffi-jni-main-03-ctor.sx` exercises both this slice and the
previous super-dispatch slice in a single `onCreate` body: calls
`super.onCreate(b)` then constructs a `SurfaceView` with the Activity
as Context. IR shows the expected six-stage chain (FindClass+GetMethodID+
CallNonvirtual + FindClass+GetMethodID+NewObject); APK builds clean.
Naming caveat: the Java type `android.content.Context` clashes with
sx stdlib's `Context :: struct {...}` (heap-context). The smoke aliases
it `JContext` — future work could add a path-prefix or `as` rename
form on `#jni_class` to avoid the manual rename.
133 host / 6 cross / zig build test all green.
c02b6b3b1b