Add sorting functionality to category pages

[17cupsofcoffee]

This PR adds a dropdown to category pages, allowing the crates to be sorted in various ways:

firefox_2025-01-25_19-26-26.mp4

I originally intended to use a pre-made library for this, but all the ones I could find either:

• were way too huge/complex
• only worked with tables
• only worked with JS frameworks like React

Since we're already using jQuery for other parts of the site, I decided to just take the old school approach and write some JS myself. It seems fairly snappy on desktop, though I need to give it a try on mobile too.

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I also found while working on this that Semantic UI's .cards class (which is used to create the columns on the homepage/game categories) is an absolute nightmare - it uses negative margins for everything, which breaks the layout in strange ways if you try to put any other UI near it 🙃

To get around this, I ended up replacing it with a new .card-grid class, which uses CSS Grid to create the columns. This feature is supported in 97% of browsers at this point.

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I would appreciate feedback on the UI, and whether there are other sort options that should be available!

I did originally have the option to sort by license, but the license info is a little too inconsistent for that to work (e.g. some repos have MIT and Apache, some have Apache and MIT).

[17cupsofcoffee]

I made a few more tweaks to the UI on desktop and mobile:

I think at this point, this is ready to be merged - I will wait a bit longer to see if there's any feedback first.