Lux Papers Build #102

paper: LP-7200 — on-chain checkpoint anchoring for CRDT state

8-page LaTeX paper specifying the anchor precompile at 0x0700...00 and
its integration with off-chain CRDT replicas.

Problem: when an app stores data off-chain (CRDT op logs, SQLite
replicas, IPFS blobs), users need a way to prove the server hasn't
silently rewritten history. Anchoring the state's Merkle root to a
public chain at known heights gives tamper-evident durability without
putting every op on-chain.

Design:
- 72-byte payload (appID 32 + height 8 + root 32) → single tx.
- Height monotonicity enforced on-chain: retroactive rewrites revert.
- Q-Chain is the recommended anchor target (PQ finality, near-zero
  gas); C-Chain is the fallback for apps already paying gas there.
- Batched (1000 docs, Merkle root of anchors-per-batch): ~$0.000001
  per anchor amortised.

Verification: eth_call to get(appID, height), compare to local root.
Zero gas, ~50 ms round-trip.

Implementation: luxfi/precompile@5eb5ce4; SDK hanzo/base/crdt@HEAD.