GreenField API: Wallet API (#2246)

* GreenField: Wallet API

* more work

* wip

* rough fiunish of transaction sending api

* Allow to create tx without broadcasting and small fixes

* Refactor Wallet Receive feature ad add greenfield api for address reserve for wallet

* add wallet api client

* add docs

* fix json converter tags

* fixes and add wallet tests

* fix tests

* fix rebase

* fixes

* just pass the tests already

* ugggh

* small cleanup

* revert int support in numeric string converter and make block id as native number in json

* fix LN endpoint

* try fix flaky test

* Revert "try fix flaky test"

This reverts commit 2e0d256325b892f7741325dcbab01196f74d182a.

* try fix other flaky test

* return proepr error if fee rate could not be fetched

* try fix test again

* reduce fee related logic for wallet api

* try reduce code changes for pr scope

* change auth logic for initial release of wallet api

BTCPayServer/Extensions/AuthorizationExtensions.cs

@@ -0,0 +1,22 @@
+using System.Security.Claims;
+using System.Threading.Tasks;
+using BTCPayServer.Client;
+using BTCPayServer.Security.Bitpay;
+using BTCPayServer.Security.GreenField;
+using BTCPayServer.Services;
+using Microsoft.AspNetCore.Authorization;
+
+namespace BTCPayServer
+{
+    public static class AuthorizationExtensions
+    {
+        public static async Task<(bool HotWallet, bool RPCImport)> CanUseHotWallet(
+            this IAuthorizationService authorizationService,
+            PoliciesSettings policiesSettings,
+            ClaimsPrincipal user)
+        {
+            return (await authorizationService.AuthorizeAsync(user, Policies.CanModifyServerSettings))
+                .Succeeded ? (true, true) : (policiesSettings?.AllowHotWalletForAll is true, policiesSettings?.AllowHotWalletRPCImportForAll is true);
+        }
+    }
+}