Resolve fees for pre-662000 witness-hash transactions

[droplister]

What this fixes

932 transactions between blocks 557,368 and 661,989 carried a witness hash (wtxid) as their Counterparty tx_hash. Electrs, mempool.space and blockstream.info all 404 on them permanently. They sat at the top of transactions WHERE fee IS NULL ORDER BY tx_index DESC and ate the entire fee-backfill budget every cron tick — requested: 1000, updated: 0 after 128 s — so the runner never reached the 1.08M pre-segwit rows below them.

Root cause (upstream, and permanent)

counterparty-core/counterpartycore/protocol_changes.json:

"correct_segwit_txids": { "block_index": 662000, "minimum_version_minor": 59 }

counterparty-rs/src/indexer/bitcoin_client.rs:907:

let tx_id = tx.compute_txid().to_string();
if segwit && config.correct_segwit_txids_enabled(height) {
    tx_hash = tx_id.clone();                            // >= 662000: the real txid
} else {
    tx_hash = Sha256dHash::hash(&tx_bytes).to_string(); // full bytes incl. witness = the wtxid
}

That else branch is still in current master by design — these hashes are consensus identity throughout the ledger (sends, orders, dispensers reference them), so the fix is forward-only and history can never be rewritten. No node upgrade will change these values; the live node is on 11.3.0 and still serves the wtxid for them, correctly.

So the mirror keeps the wtxid (CLAUDE.md rule 7 — raw 1:1 capture) and only the derived fee is repaired.

The footprint matches the protocol gate exactly on both ends: 932 missing rows below block 662,000, 0 at or above it; highest 661,989 (eleven blocks before activation), lowest 557,368 (just after segwit_support at 557,236).

Approach

No Bitcoin node needed. For each affected block: fetch the raw block, compute both identities for every transaction — txid from the serialization without witness, wtxid from the full serialization — match ours by wtxid, then read the fee from the canonical txid. Exact by construction, no heuristic matching. Resumable via its output file.

Results

• 932/932 resolved, 0 unresolved, 0 failed blocks across 685 distinct blocks.
• Every row matched through the wtxid path — none via the txid fallback, exactly as predicted.
• 932 distinct txids (clean 1:1), no zero fees, range 113–736,011 sats.
• Five rows spot-verified against Electrs, a different provider from the one used to resolve: 5/5 exact on both fee and block height.
• Published to xcpio-core: 3,708 writes = 932 rows × 4 (row + 3 trigger writes), guarded with WHERE fee IS NULL.
• Missing fees above block 550,000: now 0. Highest remaining is 547,696 — below segwit activation, so every remaining row is hash-fetchable.
• The trigger-maintained bitcoin_fees_remaining counter agrees exactly with COUNT(*) at 1,079,101.

Relationship to #7

Independent — different files, no conflict. #7 fixes the cron job (persisted walk cursor, tip pass, provider-budget pacing) for the remaining 1,079,101 pre-segwit rows. This PR clears the blockage that made #7's walk necessary to diagnose in the first place.

npm run check passes.

🤖 Generated with Claude Code

https://claude.ai/code/session_01VkV3DqBuyfsJj9bo76xiDM