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, 115 insertions, 0 deletions

diff --git a/docs/site.md b/docs/site.md
new file mode 100644
index 0000000..9526a61
--- /dev/null
+++ b/docs/site.md
@@ -0,0 +1,115 @@
+# Public Site Contract
+
+The public Bitflash sites are generated from this repository. If a deployed
+page and the source disagree, the deployed page is stale.
+
+## Canonical Navigation
+
+Every public page should use the same top navigation:
+
+| label | target |
+|---|---|
+| home | `https://bitflash.network/` |
+| code | `https://git.bitflash.network/bitflash/bitflash` |
+| docs | `https://docs.bitflash.network/` |
+| downloads | `https://releases.bitflash.network/` |
+| explorer | `https://explorer.bitflash.network/` |
+| status | `https://status.bitflash.network/` |
+
+The `code` link intentionally points at the repository, not the Forgejo
+instance root. A visitor choosing "code" wants the source tree.
+
+## Documentation Pages To Publish
+
+The docs index should expose these source files:
+
+| page | source | why it matters |
+|---|---|---|
+| Manual | `README.md` | run, mine, recover, operate |
+| Key derivation and address format | `docs/derivation.md` | independent wallet recovery |
+| Release verification | `docs/release-verification.md` | pinned signing-key flow |
+| Dependencies | `docs/dependencies.md` | pinned secp256k1/RandomX supply chain |
+| Rendezvous and .btf addressing | `docs/rendezvous.md` | network design and caveats |
+| Tor mode | `docs/tor.md` | `-tor`, `-socks`, onion relay operation |
+| Fair launch verifier | `docs/fair-launch.md` | no-premine launch audit |
+| UTXO set commitment | `docs/utxo-commitment.md` | deterministic supply/root audit |
+| UTXO inclusion proofs | `docs/utxo-proofs.md` | proof for one unspent output |
+| Mining calculator | `docs/mining-calculator.md` | local WhatToMine-style estimates |
+| Public pool directory | `docs/pool-directory.md` | `pool_status.json`, `pools.json`, ranking |
+
+## Release Mirror Aliases
+
+Each release remains under its versioned directory:
+
+```text
+https://releases.bitflash.network/v1.2.19/SHA256SUMS
+https://releases.bitflash.network/v1.2.19/SHA256SUMS.asc
+```
+
+The release root should also alias the latest files:
+
+```text
+https://releases.bitflash.network/SHA256SUMS
+https://releases.bitflash.network/SHA256SUMS.asc
+https://releases.bitflash.network/Bitflash-latest-windows.zip
+https://releases.bitflash.network/Bitflash-latest-x86_64.AppImage
+https://releases.bitflash.network/bitflash-node-latest-x86_64
+```
+
+The aliases are convenience only. Verification must still require the pinned
+release key documented in `docs/release-verification.md`.
+
+## Static Explorer
+
+`scripts/build-explorer.py` writes a static explorer with no backend:
+
+```text
+index.html
+style.css
+explorer.js
+logo.png
+blocks.json
+block/<height>.json
+```
+
+Serve it with a strict content policy:
+
+```text
+default-src 'none';
+img-src 'self';
+style-src 'self';
+script-src 'self';
+connect-src 'self';
+base-uri 'none';
+form-action 'none';
+frame-ancestors 'none';
+```
+
+The viewer must never use `innerHTML` for chain data. A malicious transaction
+must be rendered as text, not interpreted as markup.
+
+## Cache Policy
+
+Recommended defaults:
+
+| path | cache |
+|---|---|
+| HTML pages | `public, max-age=0, must-revalidate` |
+| `status.json` | `no-store` |
+| `blocks.json`, `block/*.json` | `public, max-age=0, must-revalidate` |
+| release assets | `public, max-age=14400, must-revalidate` |
+| `SHA256SUMS`, signatures, keys | `public, max-age=0, must-revalidate` |
+
+## Security Headers
+
+Recommended for all static pages:
+
+```text
+Strict-Transport-Security: max-age=31536000; includeSubDomains
+X-Content-Type-Options: nosniff
+Referrer-Policy: no-referrer
+Permissions-Policy: interest-cohort=(), geolocation=(), camera=(), microphone=()
+```
+
+Forgejo has its own application headers and should not blindly inherit the
+static-site CSP.