Adds deterministic HD key derivation (path m/44'/2222'/0'/0/i, matching the TRIdock web wallet) wired into CWallet: HD seed stored in wallet.dat (encrypted with the wallet master key when the wallet is encrypted), keypool derived from the seed, and new RPC commands hdnew/hdrestore/hdshow/hdinfo. Crypto core verified standalone against the official BIP39 vector and triWallet.js addresses.
Sami