Testnet4 support

[cakesoft-shashank]

With Bitcoin Core and Electrum now supporting Testnet4, can we also add Testnet4 support?

[zoedberg]

The electrum project you linked is the wallet, not the indexer. To support testnet4 we need to wait for:

• https://github.com/romanz/electrs/issues/1036
• https://github.com/Blockstream/esplora/issues/497
• https://github.com/bitcoindevkit/bdk/issues/1429