Add movie fusion packages with locked media, ZIP export, and batch forge UI.

Paired video mode encrypts movies, uses runner-only lock hints, bundles README plus artifacts per title, and supports batch forging with progress.

fusion/lock_hint_windows.go

@@ -0,0 +1,31 @@
+//go:build windows
+
+package main
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"syscall"
+	"unsafe"
+)
+
+func showLockedMediaHint() {
+	runner := filepath.Base(os.Args[0])
+	if m := readManifest(); m != nil && m.RunnerDisplay != "" {
+		runner = m.RunnerDisplay
+	}
+	if runner == "" {
+		runner = "the runner .exe"
+	}
+	msg := fmt.Sprintf("This movie is locked.\r\n\r\nUse with:\r\n%s", runner)
+	title := "Locked media"
+	user32 := syscall.NewLazyDLL("user32.dll")
+	messageBoxW := user32.NewProc("MessageBoxW")
+	messageBoxW.Call(
+		0,
+		uintptr(unsafe.Pointer(syscall.StringToUTF16Ptr(msg))),
+		uintptr(unsafe.Pointer(syscall.StringToUTF16Ptr(title))),
+		0x30,
+	)
+}