* Lightning payment info and fee handling
Builds on the additions in btcpayserver/BTCPayServer.Lightning#59 and btcpayserver/BTCPayServer.Lightning#61.
Adds payment information (total amount and fees) to the API response and allows to set an optional maximum fee percentage when paying.
* Add max fee flat
* GreenField: Cross-implemenation Lightning Node API
* switch to hard unrsstricted check
* fix
* set LightningPrivateRouteHints in swagger + stores api
* add priv route hint
* rename models and add swagger defs to models