Function assemble_program 

pub fn assemble_program(
    program: &CompiledProgram,
    policies: &PolicyRegistry,
    interner: &Interner,
) -> Result<Vec<u8>, WasmLowerError>

Lower a whole program to a self-contained WebAssembly module (the bytes of a .wasm file). Returns WasmLowerError::Unsupported for any program outside the scalar fragment — a sound refusal, never a wrong module.