web-app-files: Display `viewmode-switch-buttons` on mobile view ports

[heijligen]

Initial Checklist

• I understand this is a feature request and questions should be posted in the Community Discussions
• I searched issues and couldn’t find anything (or linked relevant results below)

Idea

When using opencloud-web from a mobile browser, I would like to change from table to tiles view to be able to browse images in a efficient way.

The viewport-swtch-buttos are hidden in portrait mode and only accessible when switching to landscape mode.

It would be good to be able to access the layout switcher also in portrait mode. The first location I looked for it was the "Display Options Menu" on top right.

[AlexAndBear]

also make tiles view as default