Add readExtraAliasEntryOld (tag 20) and readExtraAliasEntry (tag 33)
wire readers so the node can deserialise blocks containing alias
registrations. Without these readers, mainnet sync would fail on any
block with an alias transaction. Three round-trip tests validate the
new readers.
Also apply AX-2 (comments as usage examples) across 12 files: add
concrete usage-example comments to exported functions in config/,
types/, wire/, chain/, difficulty/, and consensus/. Fix stale doc
in consensus/doc.go that incorrectly referenced *config.ChainConfig.
Co-Authored-By: Virgil <virgil@lethean.io>
Rewrites the LWMA difficulty algorithm to match the C++ daemon exactly:
- Uses N=60 window with linear weighting (position 1..n)
- Clamps solve times to [-6T, 6T]
- Excludes genesis block from the difficulty window
- Selects target based on hardfork: 120s pre-HF2, 240s post-HF2
On testnet, HF2 activates at height 10 (active from height 11),
doubling the target from 120s to 240s. The previous fixed 120s target
produced exactly half the expected difficulty from height 11 onward.
Integration test verifies all 2576 testnet blocks match the daemon.
Co-Authored-By: Charon <charon@lethean.io>