hst: optionally reject insecure options

This prevents inadvertent use of insecure compatibility features.

Closes #30.

Signed-off-by: Ophestra <cat@gensokyo.uk>

internal/outcome/finalise.go

@@ -32,7 +32,14 @@ type outcome struct {
 	syscallDispatcher
 }
 
-func (k *outcome) finalise(ctx context.Context, msg message.Msg, id *hst.ID, config *hst.Config) error {
+// finalise prepares an outcome for main.
+func (k *outcome) finalise(
+	ctx context.Context,
+	msg message.Msg,
+	id *hst.ID,
+	config *hst.Config,
+	flags int,
+) error {
 	if ctx == nil || id == nil {
 		// unreachable
 		panic("invalid call to finalise")
@@ -43,7 +50,7 @@ func (k *outcome) finalise(ctx context.Context, msg message.Msg, id *hst.ID, con
 	}
 	k.ctx = ctx
 
-	if err := config.Validate(); err != nil {
+	if err := config.Validate(flags); err != nil {
 		return err
 	}