I mean, you say contradictory things in your post: you don’t want to manage a db, but you want to assign tags and categorize the photos, which would need a db of some kind.

If you really, really don’t want a db but you want web access to your pics, just rename them so they sort alphabetically the way you want and drop them in the doc root of a www server, apache or nginx would work. Do note that you will have no sorting or tagging options, but it will be dead simple. This is what the copyparty option would give you.

Not sure what you mean about “a whole Linux container”, the majority of my alpine images run in under 100MB memory and use less than 0.1% CPU, so it’s not clear to me what your objection is.