feat: add Floresta client support

[4xvgal]

feat: add Floresta client support

Summary

Add support for connecting to an external Floresta node via Electrum protocol and JSON-RPC. This allows coconut_wallet to use Floresta as a backend in regtest mode.

What's included

• Floresta-compatible Electrum server connection
• Runtime descriptor registration via Floresta JSON-RPC (loaddescriptor)
• Blockchain rescan trigger via Floresta JSON-RPC (rescan)
• RPC connection status check

Tested environment

• bitcoind v30.2
• utreexod v0.52.0
• floresta v0.9.1

Tested features

• TX pulling / balance sync
• TX broadcast (not yet implemented in this PR)

Notes

• RBF/transaction builder tests pass
• Some pre-existing/flaky tests in socket_manager_test and electrum e2e tests may fail depending on environment
• No new unit tests added for Floresta RPC client yet
• 🚨 Warning: Floresta RPC currently has no authentication. Use only on a VPN or private network. 🚨

References

• https://docs.getfloresta.sh/floresta_rpc/rpc/trait.FlorestaRPC.html
• https://github.com/getfloresta/Floresta
• https://github.com/utreexo/utreexod

Future work

Built-in Floresta node support is tracked in #<epic_issue_number>.

[4xvgal]

Test Env setup

bitcoind (regtest)
    ↓  (RPC + P2P)
utreexod (bridge mode, regtest)   ← Utreexo proof 생성
    ↓  (P2P, utreexo protocol)
florestad (regtest)               ← 경량 검증 노드

index

1. setup bitcoind with regtest network
2. setup utreexod with regtest network in bridge mode for floresta
3. setup floresta with regtest network

1. setup bitcoind with regtest network

# Ubuntu/Debian
sudo apt update
sudo apt install bitcoind

conf

mkdir -p ~/.bitcoin
cat > ~/.bitcoin/bitcoin.conf << 'EOF'
[regtest]
# RPC 설정
rpcuser=user
rpcpassword=password
rpcport=18443
rpcbind=127.0.0.1
rpcallowip=127.0.0.1

# P2P
listen=1
port=18444
bind=127.0.0.1

# utreexod가 붙을 수 있도록 zmq 또는 indexing 허용
txindex=1
server=1
EOF

execute

bitcoind -regtest -fallbackfee=0.0001 -daemon

# 지갑 생성 및 블록 마이닝 (잔액 확보)
bitcoin-cli -regtest createwallet "test"
bitcoin-cli -regtest -generate 101 

2단계 — utreexod (bridge mode, regtest)

git clone https://github.com/utreexo/utreexod.git
cd utreexod

make all

실행

./utreexod --regtest --connect=127.0.0.1:18444 --utreexoproofindex --listen=127.0.0.1:18448 --prune 0 --flatutreexoproofindex

3. Floresta

git clone https://github.com/getfloresta/Floresta.git
cd Floresta

cargo build --release

# 또는 PATH에 설치
cargo install --path ./bin/florestad --locked
cargo install --path ./bin/floresta-cli --locked

주의: macOS환경에서 iOS 시뮬레이터는 127.0.0.1 접근이 안되기 때문에 일렉트럼을 노출하는 floresta의 일렉트럼 포트와 RPC 서버는 localhost를 제외한 네트워크 환경에 바인딩 되어야함 ( 127.0.0.1 X -> 192...)

florestad -n regtest --connect 127.0.0.1:18448 --rpc-address 192.168.0.46:20002 --electrum-address 192.168.0.46:20001

주의: 만약 utreexod를 한번이라도 그냥 실행하거나 pruned 로 실행하면 full node 모드로 동작하지 않아 블록데이터를 전파하지 않음.
따라서 floresta-cli에서 bitcoind를 직접 노드 연결 추가해주면 해결됨.

floresta-cli -n regtest -H 192.168.0.46:20002 addnode 127.0.0.1:18444 add

시작 순서 요약

1. bitcoind 시작  →  블록 마이닝 (최소 101블록)
2. utreexod 시작  →  bitcoind 동기화 + proof 인덱싱 완료 확인
3. florestad 시작 →  utreexod에 연결

utreexoctl 로 블록체인 상태 보기

./utreexoctl --regtest getblockchaininfo

floresta-cli로 블록체인 상태보기

floresta-cli -n regtest -H 192.168.0.46:20002 getblockchaininfo