Copy to Clipboard Function in App.js

This issue should be resolved by creating copyToClipboard that:

Input (Password)
WriteText to Navigator Clipboard -> Password

Open App.js and locate the password input and the requested copyToClipboard entry point. Check the existing app behavior, then make the password available through the Navigator Clipboard writeText operation and verify that copying produces the generated password.

索引モデルが issue の本文から書いたものです。