[FEATURE REQUEST] - Remember selected sort order / Default sort order setting

[ReineYumiria]

Is your feature request related to a problem? Please describe.
I often browse sequential image sets such as comics or CG collections in Valv.

Currently, the gallery seems to default to "Newest first" every time.
This makes sequential image sets inconvenient to browse, because I have to go backwards through the images.

For these types of image sets, I want to view them in the natural reading order, from oldest to newest, moving left to right.

Describe the solution you'd like
I would like Valv to remember the last selected sort order for each folder or vault.

Alternatively, it would also be helpful to have a default sort order setting, such as:

• Newest first
• Oldest first
• Filename ascending
• Filename descending

For my use case, being able to keep "Oldest first" as the default would solve the issue.

Additional context
This is especially useful for imported image sets where the order matters, such as comics, CG collections, or sequential artwork.

Valv is very useful as a private gallery, so being able to preserve the browsing order would make it much more comfortable for these kinds of collections.

Thank you for developing Valv!

[ReineYumiria]

Additional context:

A similar concept exists in comic/manga readers such as Komga or Kavita.

For example, Komga's web reader supports different reading modes such as left-to-right, right-to-left, vertical, and webtoon. Kavita also has reader settings for reading direction and pagination direction.

My use case is similar: when browsing sequential image sets, the image order and swipe direction matter. If Valv always defaults to "Newest first", the set feels reversed when browsing.

References:

• Komga Webreader settings: https://komga.org/docs/guides/webreader-divina/
• Kavita Comic/Manga reader settings: https://wiki.kavitareader.com/guides/readers/comic-manga/

I do not need Valv to become a full manga reader, but remembering the selected sort order or allowing a default sort order would help with the same kind of sequential browsing use case.