Handle UNINITIALIZED and OK KV store errors

[ulyssa]

The make_fastly_kv_error doesn't handle the KV_ERROR_OK or KV_ERROR_UNINITIALIZED variants, which can happen if the hostcall fails in several unplanned ways, in which case it will return a corresponding FastlyStatus. It looks like the switch statement meant to use host_error in those cases, but the default: branch makes an internal_error instead.

I've updated the function to create a host_error and track the FastlyStatus value, which should make sure we hit this path and get the relevant status:

js-compute-runtime/runtime/fastly/host-api/host_call.cpp

Lines 39 to 42 in 363550a

	// kv error was a host call error -> report as host error
	if (err.detail == FastlyKVError::detail::host_error) {
	return handle_api_error(cx, err.host_error, line, func);
	}