Fix invoice amount for lnurlp payments

Incoming amount is msats, but we create invoices with sats.

app/controllers/lnurlpay_controller.rb

@@ -20,7 +20,7 @@ class LnurlpayController < ApplicationController
     validate_amount(amount)
 
     payment_request = @user.ln_create_invoice({
-      amount: amount,
+      amount: amount / 1000, # we create invoices in sats
       description_hash: Digest::SHA2.hexdigest(metadata(address))
     })