Show information about retries for failed payments

[Catrya]

It is happening that if a payment to the buyer fails, users cannot know how many times they will be tried to pay again, or in what time, that is because that information isn't exposed by the Mostro Daemon in the Instance Status event - https://mostro.network/protocol/other_events.html nor in the PaymentFailed message. it's just in settings.toml in the mostrod:

# Retries for failed payments
payment_attempts = 3
# Retries interval for failed payments
payment_retries_interval = 60

I suggest either sending that data in each PaymentFailed message or adding it to the instance information event.