Example "Using WASI" doesn't compile

[pebbe]

I run the example on https://tinygo.org/docs/guides/webassembly/wasi/

$ GOOS=wasip1 GOARCH=wasm tinygo build -o main.wasm main.go
main.go:4:6: can only use //go:wasmimport on declarations

tinygo version 0.41.1 linux/amd64 (using go version go1.26.5 and LLVM version 20.1.1)

main.go:

package main

//go:wasmimport yourmodulename add
func add(x, y uint32) uint32 {
	return x + y
}

// main is required for the `wasip1` target, even if it isn't used.
func main() {}