This commits does a few things:
1) Adds cache of token amount to the GetWalletToken endpoint, used by
mobile, in case the user is offline.
2) Split circuits by chain-id (when available) and by host+index when
not
3) It makes GetWalletToken always refresh, as that's directed from an
user action and we want to respect that. A cool down of 10s should be
added in the future to avoid spamming.
9e5fa3f22c