[Performance] File selection is extremely slow

[dschmidt]

Describe the bug

Selecting files should be instant, especially in the tiles view it's super slow.

Steps to reproduce

1. Upload 500 photos into one folder
2. Switch to tiles view
3. Try to select files (-> selected = checkbox is ticked)

Expected behavior

Clicking a resource instantly selects it.

Actual behavior

With 500 tiles it takes multiple seconds to select a resource on my machine.

Setup

Please describe how you started the server and provide a list of relevant environment variables or configuration files.

OCIS_XXX=somevalue
OCIS_YYY=somevalue
PROXY_XXX=somevalue

Additional context

Add any other context about the problem here.