Use merged files as primary database, deleting individual runs

Currently the data from `gts` is all stored. It would be nice to add an option to delete these YYYY-MM-DD files so that `merge` files are the final ones.

A few notes:
- [ ] `merge-csv.sh` should be modified to include the merge files (if they exist) and delete the YYYY-MM-DD files
- [ ] This should be an option within the Docker action to delete those files. Default is to keep it.