Migrate ecash-herald to in-node chronik-client
This diff is intended to maintain existing functionality of existing ecash-herald with as little refactoring as possible. New in-node chronik-client allows for many improvements to ecash-herald that will be handled in other refactors.
ALP txs now appear under "eToken sends" and not EMPP
Currently, we can detect a block that is found but rejected by avalanche bc the herald will send an error msg -- the block connects, but is not indexed, so the herald's chronik.block call fails and we see a default msg. ABC devs get what is going on but this is not clear to users.
I've added caching to preserve this alert feature. When a block is connected, ecash-herald will wait 30s. If no finalized msg comes in, a "block connected but not finalized by avalanche for 30s" is sent.
In practical testing, the `BLK_FINALIZED` msg seems to come in only a few seconds after the `BLK_CONNECTED` msg.