//! Host callback function table for dynclib guests.
//!
//! Dynclib guests use a single business entry point plus a buffer free callback.
/// Host callback function pointer table.
///
/// # Safety
///
/// - All function pointers remain valid from `actr_init` until process exit.
/// - The host guarantees serialized entry per guest instance.
/// - All buffers returned by `invoke` must be released with `free_host_buf`.