## What happened
Double-clicking a photo in the file manager opens it in imv, but the Left/Right
arrow keys do nothing — there's no next/previous image to move to.

## Root cause
`xdg-mime query default image/jpeg` resolves to `imv.desktop`, whose Exec line is:

    imv %F

This only loads the single file passed by the file manager, so imv's image list
has exactly one entry and prev/next are no-ops.

Omarchy already ships a second entry, `imv-dir.desktop` (NoDisplay=true), whose
Exec line is:

    imv-dir %F

`/usr/bin/imv-dir` (from the imv package) resolves this correctly:

    imv -n "$1" "$(dirname "$1")"

i.e. it opens the whole containing folder, starting on the clicked photo — which
is what makes arrow-key navigation work.

## Expected
Opening a photo from the file manager should let you arrow through the rest of
the photos in that folder, same as most image viewers.

## Fix
Register `imv-dir.desktop` as the default handler for image mimetypes instead of
`imv.desktop` (e.g. in the omarchy package's default mimeapps.list / xdg-mime
setup).

## Workaround

    xdg-mime default imv-dir.desktop image/jpeg image/png image/gif image/webp image/bmp image/tiff image/svg+xml image/heif image/avif image/jxl image/qoi

## System
- Omarchy version: 4.0.4-1
- Channel: stable
- imv: 5.0.1-2