feat(funding-service): collect deposits sent to the funding account

[SantiagoPittella]

Summary

Adds funding for the funder account via a public pay-to-ID note holding the native asset, and the service finds and consumes it on its own.

Only public, pay-to-ID, targeting the funding account, holding nothing but the native asset are collected.

Deposits are consumed in their own transaction, so a note that turns out to be unconsumable cannot fail a request a client is waiting on.

--top-up-interval controls how often it runs, defaulting to one minute.

Changelog

[[entry]]
scope       = "funding-service"
impact      = "added"
description = "The service collects public pay-to-ID deposits sent to its funding account."