Looking for free online service or Linux tool to archive/search my Lemmy saved posts for multiple instances

I’m trying to find a way to archive all my saved Lemmy posts from multiple instances in one place, and be able to search through them by tags, title, body text, date, etc.

Does anyone know of a free online service or a local Linux tool that can?

• fetch and store saved posts from all instances I’m active on,
• let me query/search effectively (tags, title, content, date, etc.).

Thanks in advance!