Bring main onto the line this project actually ships

main had drifted to a history with no ancestor in common with the tree we
build and deploy. It sat at be63e83 (2026-08-09) with 28 commits; the shipped
line, deploy/soak-2026-08-21, had 383. The two shared nothing -- git
merge-base returns no result at all -- so anyone cloning this repository
landed on a default branch that was neither current nor related to the
running node.

The 28 commits on main were audited before this merge: every one is already
present in the tree by content, including the two that are hardest to see
because they were rewritten afterwards -- the payout reorg-safety work
(PayoutBlockStillOnChain, since evolved to re-check on every retry rather
than once at maturity) and the nostr relay certificate verification
(SSL_set1_host, now with a Windows root-store path). Nothing on main is lost
by this merge.

Recorded as a merge rather than a force-push: main only ever moves forward,
its old history stays reachable as the first parent, and this is revertible.
The tree is taken wholesale from the merged branch, so main's content is now
exactly what was built and tested.

What this brings onto main:

- compactblock: BIP152-style compact block relay ported from upstream 1.2.23,
  primitives and unit test only, with the RAND_bytes failure path closed and
  the reconstruction allocation bounded.
- upstream/main 17741d9: isolated testnet parameters and genesis, optional
  2 MB large pages for RandomX. Mainnet genesis verified byte-identical
  through upstream's BuildGenesisBlock() refactor.
- deploy: every image built on bookworm so binaries run on Debian 12, and the
  container build now honours the RandomX and libsecp256k1 pins it had been
  silently ignoring since before 1.2.15.

Gates at this tree: 15/15 selftests, compactblock's 17 checks, consensus
constants unchanged against e4f898c apart from the pre-existing
MAX_BLOCK_SIZE_GEN, mainnet genesis intact, money-log check ok.

1 files changed, 70 insertions, 0 deletions

diff --git a/docs/fair-launch.md b/docs/fair-launch.md
new file mode 100644
index 0000000..9603910
--- /dev/null
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+# Bitflash fair-launch verifier
+
+Bitflash ships a deterministic fair-launch audit script:
+
+```bash
+python3 scripts/verify-fair-launch.py --max-blocks 1000 --out bitflash-fair-launch-report.json --json
+```
+
+The verifier reads `blk*.dat` directly from the local Bitflash data directory.
+It does not use Berkeley DB, does not call the node binary, and does not need
+network access. It uses the same shared Python chain parser as the UTXO
+commitment and proof tools, so block serialization fixes land in one place.
+
+The report proves the launch baseline that can be checked from the chain:
+
+- the genesis block hash matches the source constant;
+- the genesis merkle root matches the source constant;
+- the genesis transaction is a single coinbase transaction;
+- the genesis output total is exactly `50.00000000 BTF`;
+- the scanned block range and mined coinbase total are reproducible.
+
+For machines that do not have a synced data directory yet, the source constants
+can be checked without disk blocks:
+
+```bash
+python3 scripts/verify-fair-launch.py --reconstruct-genesis
+```
+
+## Deterministic output
+
+Use `--json` or `--out` for canonical JSON. The JSON is written with sorted
+keys, fixed separators, ASCII escaping, and one trailing newline. It deliberately
+does not include local paths or wall-clock generation time, so two auditors
+scanning the same block range produce the same bytes.
+
+That makes the report shareable:
+
+```bash
+python3 scripts/verify-fair-launch.py --max-blocks 1000 --out report.json --json
+sha256sum report.json
+```
+
+If another auditor runs the same command against the same chain prefix, the
+`sha256sum` should match.
+
+## OpenTimestamps
+
+OpenTimestamps is optional and external. It anchors the report in Bitcoin
+without adding any bridge or dependency to Bitflash consensus.
+
+After generating a canonical JSON report:
+
+```bash
+ots stamp report.json
+ots verify report.json.ots
+```
+
+The `.ots` file proves that the exact report bytes existed no later than the
+Bitcoin block that confirms the timestamp.
+
+## What this does not claim
+
+This is not a retroactive genesis commitment. The Bitflash genesis block already
+exists, so adding a new on-chain commitment to genesis would create a different
+chain. This verifier instead audits the launch state that is already on-chain
+and makes the result reproducible and timestampable.
+
+It also does not prove real-world miner identity. It proves the genesis state,
+the absence of non-coinbase premine in genesis, and the deterministic coinbase
+totals over the scanned prefix.