Display LN address as QR code and copy button

[nejos97]

• Currently, LN addresses are displayed only as text.

• Objective: Improve UX by showing QR code + text with copy button.

• Features:

  1. When a user clicks an LN address, open a dedicated page.
  2. Display the QR code for the LN address.
  3. Display the address as text with a copy button.