Curated lists should be searchable by start date, not upload date

One issue we've heard about regarding curated lists is that currently the curated lists are organized by the date they were uploaded, rather than the creation or start date of the document. Older documents that are uploaded after more recent documents will show up above the newer documents because they were migrated or uploaded more recently.

Expected behavior: Curated lists would be organized by creation date or start date of document, rather than date uploaded.

**JIRA ticket #:** DP-7436

No files, tests, or entry points are named in the issue. Start by reviewing Jira ticket DP-7436 and identifying where curated-list ordering is defined; done means lists are ordered by the document creation or start date instead of upload date, including migrated documents.

Written by the indexing model from the issue text.