Burn it all down and rewrite in Svelte 5

[diamondburned]

JavaScript has failed us, yet again. Migrating from Svelte 4 to Svelte 5 and reworking the entire windowing system is proving to be too difficult to be lumped up in a single task.

Let's wipe all the old frontend code and write fresh Svelte 5 code from the start, this time with the intended windowing system. We'll make certain guarantees to keep track of the windowing state so that our objectives with the new windowing system can be met:

• It needs to be able to spawn unlimited windows
• Of the same, or different types
• It needs the same degree of freedom as before
  • Minimizing, maximizing, closing
  • Moving around

:3