feat(cua): release 0.38.0+artemis.1 with verified shell observation

Upgrade the pinned driver, validate menu and taskbar focus ownership, patch untitled Shell resolution, and remove duplicate scroll scaling. Publish package provenance, verification boundaries and matching marketplace checksum. Go tests, vet, build and byte-level package verification passed.

plugins/cua-driver/shell_windows.go

@@ -0,0 +1,105 @@
+package main
+
+import (
+	"path/filepath"
+	"runtime"
+	"sync"
+	"syscall"
+	"unsafe"
+)
+
+type windowRect struct{ left, top, right, bottom int32 }
+
+func windowClass(hwnd int64) string {
+	var value [256]uint16
+	user32.NewProc("GetClassNameW").Call(uintptr(hwnd), uintptr(unsafe.Pointer(&value[0])), uintptr(len(value)))
+	return syscall.UTF16ToString(value[:])
+}
+
+func nativeWindowInfo(hwnd int64) obj {
+	if hwnd == 0 {
+		return obj{}
+	}
+	var pid uint32
+	thread, _, _ := user32.NewProc("GetWindowThreadProcessId").Call(uintptr(hwnd), uintptr(unsafe.Pointer(&pid)))
+	if pid == 0 {
+		return obj{}
+	}
+	visible, _, _ := user32.NewProc("IsWindowVisible").Call(uintptr(hwnd))
+	owner, _, _ := user32.NewProc("GetWindow").Call(uintptr(hwnd), 4)
+	root, _, _ := user32.NewProc("GetAncestor").Call(uintptr(hwnd), 2)
+	var title [1024]uint16
+	user32.NewProc("GetWindowTextW").Call(uintptr(hwnd), uintptr(unsafe.Pointer(&title[0])), uintptr(len(title)))
+	app := ""
+	process, _, _ := kernel32.NewProc("OpenProcess").Call(0x1000, 0, uintptr(pid))
+	if process != 0 {
+		var path [32768]uint16
+		size := uint32(len(path))
+		ok, _, _ := kernel32.NewProc("QueryFullProcessImageNameW").Call(process, 0, uintptr(unsafe.Pointer(&path[0])), uintptr(unsafe.Pointer(&size)))
+		if ok != 0 {
+			app = filepath.Base(syscall.UTF16ToString(path[:]))
+		}
+		kernel32.NewProc("CloseHandle").Call(process)
+	}
+	info := obj{"pid": int64(pid), "window_id": hwnd, "thread_id": int64(thread),
+		"root_window_id": int64(root), "owner_id": int64(owner), "class_name": windowClass(hwnd),
+		"title": syscall.UTF16ToString(title[:]), "app_name": app, "is_on_screen": visible != 0,
+		"z_index": nil, "minimized": false}
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+	previous, _, _ := user32.NewProc("SetThreadDpiAwarenessContext").Call(^uintptr(3))
+	if previous != 0 {
+		defer user32.NewProc("SetThreadDpiAwarenessContext").Call(previous)
+		var rect windowRect
+		ok, _, _ := user32.NewProc("GetWindowRect").Call(uintptr(hwnd), uintptr(unsafe.Pointer(&rect)))
+		if ok != 0 {
+			info["bounds"] = obj{"x": rect.left, "y": rect.top, "width": rect.right - rect.left, "height": rect.bottom - rect.top}
+			info["is_on_screen"] = visible != 0 && rect.right > rect.left && rect.bottom > rect.top
+		}
+	}
+	return info
+}
+
+// A single static callback avoids NewCallback's non-reclaimable slot leak.
+var shellEnumerationLock sync.Mutex
+var shellEnumeration *[]obj
+var shellEnumerator = syscall.NewCallback(func(hwnd, _ uintptr) uintptr {
+	if shellKind(windowClass(int64(hwnd))) != "" {
+		info := nativeWindowInfo(int64(hwnd))
+		if info["is_on_screen"] == true {
+			*shellEnumeration = append(*shellEnumeration, info)
+		}
+	}
+	return 1
+})
+
+func nativeShellWindows() []obj {
+	shellEnumerationLock.Lock()
+	defer shellEnumerationLock.Unlock()
+	var windows []obj
+	shellEnumeration = &windows
+	user32.NewProc("EnumWindows").Call(shellEnumerator, 0)
+	shellEnumeration = nil
+	return windows
+}
+
+func keyboardFocus() obj {
+	foreground := nativeWindowInfo(foregroundWindow())
+	var gui struct {
+		size, flags                                        uint32
+		active, focus, capture, menuOwner, moveSize, caret uintptr
+		rect                                               windowRect
+	}
+	gui.size = uint32(unsafe.Sizeof(gui))
+	ok, _, _ := user32.NewProc("GetGUIThreadInfo").Call(0, uintptr(unsafe.Pointer(&gui)))
+	result := obj{"probe_ok": ok != 0, "foreground_window": foreground}
+	if ok != 0 {
+		focused := nativeWindowInfo(int64(gui.focus))
+		result["focus_window"] = focused
+		result["focus_root"] = nativeWindowInfo(num(focused["root_window_id"]))
+		result["active_window"] = nativeWindowInfo(int64(gui.active))
+		result["menu_owner"] = nativeWindowInfo(int64(gui.menuOwner))
+		result["menu_active"] = gui.flags&0x1c != 0
+	}
+	return result
+}