generalize trigger kinds

daemon/job/trigger/cron.go

@@ -0,0 +1,23 @@
+package trigger
+
+import (
+	"context"
+
+	"github.com/robfig/cron/v3"
+)
+
+type Cron struct {
+	spec cron.Schedule
+}
+
+var _ Trigger = &Cron{}
+
+func NewCron(spec cron.Schedule) *Cron {
+	return &Cron{spec: spec}
+}
+
+func (t *Cron) ID() string { return "cron" }
+
+func (t *Cron) run(ctx context.Context, signal chan<- struct{}) {
+	panic("unimpl: extract from cron snapper")
+}