feat: add scheduled automatic task matching

internal/store/tasks_test.go

@@ -0,0 +1,15 @@
+package store
+
+import "testing"
+
+func TestRandomDelaySeconds(t *testing.T) {
+	for index := 0; index < 100; index++ {
+		value := randomDelaySeconds(900, 1200)
+		if value < 900 || value > 1200 {
+			t.Fatalf("delay out of range: %d", value)
+		}
+	}
+	if value := randomDelaySeconds(30, 30); value != 30 {
+		t.Fatalf("fixed delay = %d, want 30", value)
+	}
+}