refactor: implement cross-platform abstraction for process management, media control, and startup configuration (TESTING)

internal/platform/platform_windows.go

@@ -0,0 +1,32 @@
+//go:build windows
+package platform
+
+import "wis-free-v3/internal/windows"
+
+func NewOverlay() Overlay {
+	return windows.NewOverlay()
+}
+
+func PauseMedia() bool {
+	return windows.PauseMedia()
+}
+
+func ResumeMedia(wasPaused bool) {
+	windows.ResumeMedia(wasPaused)
+}
+
+func AddToStartup() error {
+	return windows.AddToStartup()
+}
+
+func RemoveFromStartup() error {
+	return windows.RemoveFromStartup()
+}
+
+func IsInStartup() bool {
+	return windows.IsInStartup()
+}
+
+func IsProcessRunning(pid int) bool {
+	return windows.IsProcessRunning(pid)
+}