## Problem
When the workflow ran on a schedule, the `region_id` input was not set.
As a result, an empty region value was used, which caused errors during
execution.
## Summary of Changes
- Added fallback logic to set a default region (`aws-us-east-2`) when
`region_id` is not provided.
- Ensures the workflow works correctly both when triggered manually
(`workflow_dispatch`) and on schedule (`cron`).
498d852bde