BUG: Albums advertise video organization but only support images

### Is there an existing issue for this?

- [x] I searched the issue tracker for this exact mismatch. The closest result is the closed broad album feature issue #775; this report is limited to the remaining, user-visible inconsistency.

### What happened?

The Create Album dialog tells users that albums organize both photos and videos, but the current implementation only permits images. A user can reasonably expect a video to be selectable for an album after reading the dialog, yet there is no UI or backend representation for a video membership.

### Evidence on `main`

- `frontend/src/components/Albums/CreateAlbumDialog.tsx:103` displays: "Create a new album to organize your photos and videos."
- `frontend/src/components/Albums/AddImagesToAlbumDialog.tsx` fetches only `fetchAllImages()` and submits only `image_ids`.
- `backend/app/database/albums.py` defines `album_images` with `image_id` as a foreign key to `images(id)`.
- `backend/app/routes/albums.py:125-126` explicitly documents that clips are left out because albums have no video support.
- `backend/app/utils/memory_scoring.py:61-65` also treats `in_album` as unavailable for videos because a video cannot be put in an album.

### Expected behavior

The UI should not claim a capability that the product does not provide. Maintainers can choose one of two directions:

1. Correct the wording so albums are accurately presented as photo-only; or
2. Scope a follow-up feature for genuine video membership in albums, including storage, API, gallery, and test coverage.

### Screenshots

Not applicable: the mismatch is visible in the create-album dialog copy and confirmed by the associated code paths above.

### Record

- [x] I agree to follow this project's Code of Conduct
- [x] I want to work on this issue

I will wait for maintainer review and direction before opening a PR.