* Histograms: Add Lightning data and API endpoints
Ported over from the mobile-working-branch.
Adds histogram data for Lightning and exposes the wallet/lightning histogram data via the API. It also add a dashboard graph for the Lightning balance.
Caveat: The Lightning histogram is calculated by using the current channel balance and going backwards through as much invoices and transactions as we have. The "start" of the LN graph data might not be accurate though. That's because we don't track (and not even have) the LN onchain data. It is calculated by using the current channel balance and going backwards through as much invoices and transactions as we have. So the historic graph data for LN is basically a best effort of trying to reconstruct it with what we have: The LN channel transactions.
* More timeframes
* Refactoring: Remove redundant WalletHistogram types
* Remove store property from dashboard tile view models
* JS error fixes
* 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
