Function compute_parameter_hash 

pub fn compute_parameter_hash(
    tool_server: &str,
    tool_name: &str,
    arguments: &Value,
    governed_intent: Option<&GovernedTransactionIntent>,
) -> String

Compute the parameter hash that binds an ApprovalRequest to a specific set of arguments. Input is canonicalized via the existing sha256_hex(chio_core::canonical::canonical_json_bytes(..)) helper so independent kernels produce identical hashes.