Photo Gallery Improvements

Extends: Issue #7
From: PR https://github.com/CivicTechTO/civic-spark.com/pull/8#pullrequestreview-3152042332

> Looks great and appears to perform really well!
>
> Nice to haves - can be added now or in future updates if desired:
>
> * Photographer credit?
> * Some delineation / indication between day 1 and 2 photos?
> * Is there some way to cache the image processing in the repo itself? It took 52 seconds to process on my first run.

To Do Items:

- [x] Photographer credit: https://www.jaxvu.com
- [ ] image processing run optimization – caching? _(relevant if work on the site continues – low value if we're at the end of development)_
- [x] day 1 and day 2 photo distinction _(nice to have)_

Start with the image-processing work associated with PR #8 and review the linked discussion. Measure the current first-run processing time, reported as 52 seconds, and determine whether caching is still valuable. Done means repeated processing avoids unnecessary work and the optimization is verified against the existing workflow.

Written by the indexing model from the issue text.