41e4a8141f
46 tests across three classes: TestBitcoinPurpleConstants — validates all BTCP network constants against the technical specification: NET_NAME, TESTNET flags, CLI flags, address prefixes (P2PKH 56, P2SH 55, WIF 0xb7), bech32/BOLT11 HRP, genesis hashes and wire-order chain_hash, default ports, PoW parameters (adj_interval 120, target_timespan 7200, MAX_TARGET, POW_GENESIS_BITS), SLIP-0132 HD key headers, LN parameters, NETS_LIST uniqueness, and inheritance independence. TestBitcoinPurpleDifficultyAdjustment — tests the 120-block retarget logic using BitcoinPurple mainnet (testnet was wrong because get_target always returns 0 on testnet). Covers: genesis index returns genesis target from POW_GENESIS_BITS, on-time/fast/slow adjustments, lower and upper clamp, the 120-block window (not 2016), and can_connect() calling get_target with the correct period index. TestBitcoinPurpleAddress — tests address encoding under BitcoinPurple: P2PKH starts with 'P', bech32 with HRP 'btcp', address_to_script produces correct P2WPKH scriptPubKey, WIF round-trip with prefix 0xb7, Bitcoin addresses rejected on BTCP network