Payment by NFC with #nostr #safebox

I have the secure plumbing figured out. Still more to implement but here is the gist:

1. Reader acquires encrypted token from card and amount

2. Generates lightning invoice.

3. Acquited sends encrypted token and invoice to token vault endpoint

4. Vault decrypts token and issues nwc command to pay invoice

5. Wallet pays invoice

6. Poll invoice and notify user invoice is paid.