feat(sdk-coin-flrp): implement UTXO address sorting to ensure signature verification

[mohd-kashif]

• Added sortAddressesByHex and sortAddressBuffersByHex utility functions to sort addresses lexicographically by byte value.
• Updated AtomicTransactionBuilder to sort UTXO addresses before computing addressesIndex, ensuring alignment with on-chain storage order.
• Introduced computeAddressesIndexFromParsed method for consistent address indexing when parsing existing transactions.
• Removed redundant computeAddressesIndexFromParsed methods from ExportInPTxBuilder and ImportInCTxBuilder.
• Added unit tests to verify address sorting functionality and its impact on transaction building for both ExportInP and ImportInC transactions.