Validate a cryptocurrency address with full checksum verification (not just regex). Returns {chain, address, valid, canonical, format, reason}. Chains: btc (P2PKH, P2SH, Bech32 SegWit v0, Taproot Bech32m), eth (full EIP-55 checksum; non-checksummed flagged), sol (Ed25519 32-byte Base58), ltc (Base58Check L.../M.../3... + ltc1 Bech32), trx (T-prefix Base58Check 0x41), xrp (r-prefix custom Base58), bch (legacy Base58Check + bitcoincash:q... CashAddr). Catches typos via cryptographic checksum; canonical field returns the checksummed/lowercased form.