Better modularize clipboard code (add "clip" package; break up TOTP code

clip/copyWIN.go

@@ -0,0 +1,28 @@
+//go:build windows || (linux && wsl)
+
+package clip
+
+import (
+	"errors"
+	"fmt"
+	"os/exec"
+	"strings"
+)
+
+// CopyString copies a string to the clipboard.
+func CopyString(continuous bool, copySubject string) error {
+	cmd := exec.Command("powershell.exe", "-c", fmt.Sprintf("echo '%s' | Set-Clipboard", strings.ReplaceAll(copySubject, "'", "''")))
+	err := cmd.Run()
+	if err != nil {
+		return errors.New("unable to copy to clipboard: " + err.Error())
+	}
+	if !continuous {
+		LaunchClipClearProcess(copySubject)
+	}
+	return nil
+}
+
+// getClipCommands returns the commands for pasting and clearing the clipboard contents.
+func getClipCommands() (*exec.Cmd, *exec.Cmd) {
+	return exec.Command("powershell.exe", "-c", "Get-Clipboard"), exec.Command("powershell.exe", "-c", "Set-Clipboard")
+}