Stacks Calldata Encoder

Encode the function arguments for a Stacks Clarity contract-call into serialized Clarity values plus a ready-to-sign contract-call spec — the Stacks analogue of the EVM Calldata Encoder (Stacks has no flat calldata blob; a contract-call's payload is a function name + a list of serialized Clarity values). Fetches the contract ABI from Hiro, coerces each argument to a ClarityValue against its declared type (recursively for optional, tuple, and list types), and returns the serialized hex per argument together with a contract-call spec (contract address, contract name, function name, and function_args as {type, value} objects) that mirrors the wallet contract-call pipeline. Pass plain values in ABI order: numbers for uint/int, strings for principal and string types, 0x-hex or text for buffers, null for an optional none, an object for a tuple, an array for a list. Read-only — it only serializes the args; it never signs or broadcasts. Pair with a simulator before signing.